Add row context menus, fix glyphicon copy corruption, combine CC email editing

- Fuchs/gulpfile.js: pass encoding:false to gulp.src() in the copy task —
  vinyl-fs otherwise UTF-8-decodes binary files by default, which was
  silently corrupting the glyphicons webfont (and any other binary asset
  copyconfig.json matches) on every `gulp copy`/`gulp all` run.
- Invoice/reminder editor: replace the row's flat action icons (edit/
  delete/insert/set-price) with a single context button opening a
  dropdown menu, reusing the existing $ocms.menu toolbar mechanism.
- Fix "-1" leaking into the Pos. column for Text/Title rows: $inv.rrw's
  `dta.position || dta.SortOrder` fallback treated the numbering's
  intentional empty string as unset and fell back to SortOrder (-1 for
  such rows); now only a genuinely uncomputed position falls back.
- Zusatzempfänger (CC) is now edited together with the main invoice
  email in one combined dialog ($inv.emailFrm/$inv.eEmail), wired into
  all three entry points (create, continue, storno) instead of a
  separate hover-revealed row with its own edit target.
- Add tooltips to every row/header edit control, including several that
  had none before (header field pencils, the request/section title
  edit button), phrased as object+verb ($rct.frmTT).

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

Fuchs/gulpfile.js

@@ -147,7 +147,11 @@ gulp.task("copy", async () => {
     const jobs = [];
     for (const cpy of copyconfig) {
         jobs.push(
-            pipeline(gulp.src(cpy.src, { allowEmpty: true }), gulp.dest(cpy.dest), preservetimeSafe(), logSink("Copied: "))
+            /* encoding:false is required — vinyl-fs otherwise UTF-8-decodes every file by default,
+               which corrupts binary assets (fonts, etc.) by replacing invalid byte sequences with
+               U+FFFD. This is what silently mangled the glyphicons webfont before (see "Fix
+               corrupted glyphicons webfont files causing decode failures"). */
+            pipeline(gulp.src(cpy.src, { allowEmpty: true, encoding: false }), gulp.dest(cpy.dest), preservetimeSafe(), logSink("Copied: "))
         );
     }
     await Promise.all(jobs);