Add user-defined invoice set structure dialog (ADR 0016)

Lets a back-office user correct/define which invoice line belongs to
which "set" and how deep it is nested, instead of relying only on the
implicit "everything after a Set header until the next Set" grouping
fds__prepInvoice derives. Sets may contain sets; every change applies
immediately to the cached draft session and is reflected in the editor
and PDF (ADR 0006/0008).

Backend:
- InvoiceSetStructure: pure parent-link forest (assign, change level,
  create, place/move-sibling, depth-first linearise + level recompute).
- InvoiceDraftSetStructureDeltas: new inv/dpatch targets set.assign,
  set.level, set.create, set.move.
- InvoiceSetPricing.Build is now order-preserving and nesting-aware
  (governed by the nearest converted ancestor); the set-item switch
  sums a header's transitive descendants so nested conversions never
  double-count.
- FuchsPdf indents nested set members per level, mirroring the editor.

Frontend:
- New fis.inv_sets.js: "Set-Struktur bearbeiten" dialog — per-block
  table of all lines with drag & drop reorder (before/after/into),
  ▲▼ order and ◀▶ level buttons, fold/unfold per set (view-only), and
  a create bar for new Set/Text lines. Posts one delta per action; the
  dialog is a pure view of the server state (ADR 0006).
- _Layout.cshtml / fis_main.js: cache-bust the dynamically imported
  per-module bundles (web/fis.<mdl>.<locale>.js/.css) with an asset
  version derived from the newest bundle write time, so a gulp rebuild
  is picked up without a stale cached module.

Docs: ADR 0016, live-draft-editing concept, INVOICE_SET_PRICING.md,
USER_GUIDE.md, ARCHITECTURE.md updated. Tests: InvoiceSetStructureTests
(new) + additions to InvoiceDraftServiceTests/InvoiceSetPricingTests.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Fuchs/js/intranet/modules/fis.inv_shared.js

@@ -86,7 +86,7 @@ $inv.iMn = (ix) => {
    yet been explicitly switched to a set-display mode (admin.setmode empty/undefined) — once set,
    changing it again is not supported (the user edits the line items directly instead); it
    reappears only if 'Änderungen verwerfen' reverts to a DB state that was never switched. */
-$inv.emOpt = (admin) => 'iss,p13b,ctp' + (((admin || {}).setmode || '') === '' ? ',setm' : '');
+$inv.emOpt = (admin) => 'iss,p13b,ctp,setst' + (((admin || {}).setmode || '') === '' ? ',setm' : '');
 $inv.eM = (r, re, opt) => {
     let m = [];
     if (booln(r, false) === true || booln(re, false) === true) {
@@ -104,6 +104,9 @@ $inv.eM = (r, re, opt) => {
     if ((opt || '').split(',').includes('setm') === true) {
         m.push({ lbl: $ict.setm, fnc: $inv.ssetmode });
     }
+    if ((opt || '').split(',').includes('setst') === true) {   /* user-defined set structure dialog (ADR 0016) */
+        m.push({ lbl: $ict.setst, fnc: () => $inv.sets.open() });
+    }
     if ((opt || '').split(',').includes('iss') === true) {  /* backend-authoritative draft (ADR 0006) */
         m.push({ lbl: 'Änderungshistorie', fnc: () => $inv.d.history() });
         m.push({ lbl: 'Änderungen verwerfen', fnc: () => $inv.d.discard() });
@@ -172,12 +175,13 @@ $inv.d = {
         if (typeof curVer === 'number' && typeof state.version === 'number' && state.version < curVer) {
             return;
         }
-        tbl.data('dver', state.version).data('serverSums', state.sums);
+        tbl.data('dver', state.version).data('serverSums', state.sums).data('dstate', state);
         $inv.d.footer(tbl, state.sums || {}, state.admin || {});
         $inv.d.notes(state.notes || []);
         $inv.d.validation(state.validation || []);
         $inv.d.applyItems(tbl, state.req || []);
         $inv.d.applySetDisplay(tbl, state.setDisplay || {});
+        if ($inv.sets && $inv.sets.isOpen()) { $inv.sets.render(state); }   /* the set-structure dialog is a view of the same state (ADR 0016) */
         /* Keep the menu's "Set-Preisanzeige" entry in sync with the authoritative admin.setmode:
            hides it right after a mode switch, and restores it if a discard reverted the draft to
            a DB state that was never switched (ADR 0006 backend-authoritative refresh). */
@@ -223,13 +227,15 @@ $inv.d = {
                 let changed = isNew || (dta.Type || '') !== (co.typ || '')
                     || dta.net !== val(co.v) || dta.net_val !== val(co.vt) || dta.vat_val !== val(co.vv)
                     || dta.svcnet_val !== val(co.vs) || dta.svcvat_val !== val(co.vsv)
-                    || (dta.position || '') !== (co.p != null ? co.p : '');
+                    || (dta.position || '') !== (co.p != null ? co.p : '')
+                    || (dta.lvl || 0) !== (co.lvl || 0) || (dta.SetItmId || null) !== (co.SetItmId != null ? co.SetItmId : null);
                 $.extend(dta, {
                     Id: id, Type: co.typ,
                     net: val(co.v), net_val: val(co.vt), vat_val: val(co.vv),
                     svcnet_val: val(co.vs), svcvat_val: val(co.vsv),
                     vat: co.vat, position: (co.p != null ? co.p : ''),
-                    SetItmId: (co.SetItmId != null ? co.SetItmId : null)
+                    SetItmId: (co.SetItmId != null ? co.SetItmId : null),
+                    lvl: (co.lvl || 0)                                       /* nesting depth (ADR 0016) — rendered as an indent */
                 });
                 if (isNew) { $.extend(dta, { htmltext: co.t, quantity: co.q }); }   // text only for server-created rows (e.g. the set row)
                 rw.data(dta);
@@ -311,7 +317,7 @@ $inv.d = {
     /* Map an inline recipient field to its delta target and send it. No token-guard here for the
        same reason as syncChanged: sync() waits for an in-flight seed instead of dropping the edit. */
     syncField: function (nme, val) {
-        let map = { invoicetitle: 'title', invoiceaddress: 'address', invoiceemail: 'email', loc: 'provisionlocation', provisionlocation: 'provisionlocation', provisionperiod: 'provisionperiod' };
+        let map = { invoicetitle: 'title', invoiceaddress: 'address', invoiceemail: 'email', invoiceemailcc: 'emailcc', loc: 'provisionlocation', provisionlocation: 'provisionlocation', provisionperiod: 'provisionperiod' };
         let target = map[nme]; if (!target) { return; }
         $inv.d.sync({ Target: target, Value: val });
     },
@@ -898,6 +904,7 @@ $inv.cntInv = function (data) {  //invoice continuation
             fm('adrfrm', inv.SendToAddress, 'invoiceaddress', 0, null);
             fm('locfrm', inv.ProvisionLocation, 'loc', 1, null);
             fm('emailfrm', inv.SendToEmail, 'invoiceemail', 0, null);
+            fm('emailccfrm', inv.SendToEmailCc, 'invoiceemailcc', 0, null);
             $$.dc('sndfrm', frm).append($$.dc('content').text(response.admin.sender));
 
             fm('admfrm', inv.ProvisionPeriod, 'provisionperiod', ((inv.ProvisionPeriod || '').includes('-') === true ? $rct.provP : $rct.provD), 1, null);
@@ -960,6 +967,7 @@ $inv.cSt = function (data) {
                     fm('adrfrm', inv.SendToAddress, 'invoiceaddress', 0, null);
                     fm('locfrm', inv.ProvisionLocation, 'loc', 1, null);
                     fm('emailfrm', inv.SendToEmail, 'invoiceemail', 0, null);
+            fm('emailccfrm', inv.SendToEmailCc, 'invoiceemailcc', 0, null);
                     $$.dc('sndfrm', frm).append($$.dc('content').text(response.admin.sender));
 
                     fm('admfrm', inv.ProvisionPeriod, 'provisionperiod', ((inv.ProvisionPeriod || '').includes('-') === true ? $rct.provP : $rct.provD), 1, null);
@@ -1101,7 +1109,7 @@ $inv.eHtml = function (ev) {
        Leistungsdatum). The backend sanitises HTML too (single source of truth, ADR 0006), but
        keeping these plain here avoids the UI briefly holding the wrapped value. Multi-line fields
        (invoiceaddress, loc) stay HTML-capable and are normalised to newlines server-side. */
-    let isPlainText = ['invoiceemail', 'provisionperiod', 'invoicetitle'].includes(ev.data.nme);
+    let isPlainText = ['invoiceemail', 'invoiceemailcc', 'provisionperiod', 'invoicetitle'].includes(ev.data.nme);
     let flds = isPlainText
         ? [{ name: 'txt', label: 'Text', type: 'text', value: frmct.text() }]
         : [{ name: 'txt', label: 'Text', type: 'html', value: frmct.html(), tinymce: true, attr: { style: 'height: 300px' } }];
@@ -1234,7 +1242,7 @@ $inv.rrw = function () {
     } else if (rw.is('.itm.osum') === true) {
         co = { invrqid: dta.InvRqId, id: 'osum' + rw.index(), typ: 'osum', p: '', q: null, t: oHtml(dta.tbl.tbl), tt: null, v: null, vt: dta.net_val, vs: dta.svcnet_val, vat: dta.vat, vv: dta.vat_val, vsv: dta.svcvat_val, det: false };
     } else {
-        co = { invrqid: dta.InvRqId, id: dta.Id || '', typ: dta.Type || 'other', p: '', q: null, t: '', tt: null, v: null, vt: dta.net_val, vs: dta.svcnet_val, vat: dta.vat, vv: dta.vat_val, vsv: dta.svcvat_val, det: (dta.Note || '') !== '' && hn === false, SetItmId: dta.SetItmId || null };
+        co = { invrqid: dta.InvRqId, id: dta.Id || '', typ: dta.Type || 'other', p: '', q: null, t: '', tt: null, v: null, vt: dta.net_val, vs: dta.svcnet_val, vat: dta.vat, vv: dta.vat_val, vsv: dta.svcvat_val, det: (dta.Note || '') !== '' && hn === false, SetItmId: dta.SetItmId || null, lvl: (dta.lvl || 0) };
         $$.dc('ibtn ico move', axf, { title: $rct.mR }); /* should be the last added */
 
         co.p = dta.position || (dta.SortOrder || '');
@@ -1274,6 +1282,7 @@ $inv.rrw = function () {
     }
     rw.empty().attr('class', ph ? 'placeholder' : 'itm').aC(co.Typ)
         .tC('sethdr', (co.typ || '').toString().toLowerCase() === 'set')   /* emphasise set rows (fn1 header + block set row) */
+        .aC((co.lvl || 0) > 0 ? 'lvl' + Math.min(co.lvl, 6) : '')          /* indent nested set members (ADR 0016) */
         .tC('hidenote', hn).append(tda);
     dta.co = co;
 };
@@ -1304,8 +1313,23 @@ $inv.invSumUpdate = function () {
     let tbl = $(this);
     let ba = [];
     let bds = tbl.children('tbody');
+    /* Hierarchical position numbering (ADR 0017), spanning the whole invoice: a running counter
+       per nesting depth, ported from InvoiceLineNumbering.Compute. A set header gets a number at
+       its own level ("3"); its members get subsidiary numbers one level deeper ("3.1", "3.2"). A
+       row's numbering never depends on the MFR SortOrder value — including for a Text/Title
+       header row synced with SortOrder -1, which used to leak "-1" straight into the Pos. column
+       here because it never went through this loop at all. */
+    let posCounters = [];
+    let nextPositionLabel = (numbered, lvl) => {
+        if (!numbered) { return ''; }
+        let l = Math.max(lvl || 0, 0);
+        while (posCounters.length <= l) { posCounters.push(0); }
+        posCounters.length = l + 1;
+        posCounters[l]++;
+        return posCounters.join('.');
+    };
     bds.each((bi, bdy) => {
-        let b = $(bdy), rx = b.data() || {}, i = [], citems = [], itm = b.find('tr.itm'), iso = 0, ipos = 0;
+        let b = $(bdy), rx = b.data() || {}, i = [], citems = [], itm = b.find('tr.itm');
         b.tC('empty', itm.length < 1);
         itm.each((ti, tx) => {
             let rrx = $(tx).data() || {};
@@ -1318,14 +1342,12 @@ $inv.invSumUpdate = function () {
                by the id !== '' && !== citem.id check below). */
             let citem = $inv.itemToContract(rrx);
             let sid = (rrx.SetItmId || '').toString();
-            if (citem.type !== 'set' && sid !== '' && sid !== citem.id) { citem.setId = sid; }
+            /* a nested set (ADR 0016) is itself a member of its parent set, so the type is not excluded here */
+            if (sid !== '' && sid !== citem.id) { citem.setId = sid; }
             citems.push(citem);
-            if (((typeof rrx.SortOrder === 'undefined' || rrx.SortOrder === null) ? -1 : rrx.SortOrder) > -1) {
-                if (['text', 'title'].includes((rrx.Type || 'other').toLowerCase()) === false) { ipos++; }
-                rrx.SortOrder = iso;
-                rrx.position = ipos;
-                $inv.rrw.call(tx);
-            }
+            let numbered = ['text', 'title'].includes((rrx.Type || 'other').toLowerCase()) === false;
+            rrx.position = nextPositionLabel(numbered, (rrx.co || {}).lvl || 0);
+            $inv.rrw.call(tx);
         });
         ba.push({ Id: rx.Id, nme: rx.Name, text: rx.text, itm: i, items: citems });
     });