feat: migrate DB error logging onto the generic OCORE MultiLogger SQL sink

Retires Fuchs_intranet.debug_log() and every direct EXECUTE [dbo].[fds__admin_logdebug]
call in favor of a single path: ILogger. A new SQL log sink (OCORE.MultiLogger.SqlLoggerProvider,
gated by Fuchs:Logging:SqlSink:Enabled, default on) mirrors every _logger.LogWarning/-Error/
-Critical call into [dbo].[fds__debuglog] via a new fds__admin_logdebug_ext proc, at Warning+.

- Program.cs registers the sink and RequestLogScopeMiddleware (request id/path/authenticated
  user, pushed after UseAuthentication) so every log line in a request — including ones written
  deep inside OCORE's SQL helpers — is attributed automatically.
- FIS_SQLOptions, IntranetController.Do's catch-all, PdfPreviewAsync, and the banking-upload
  handlers now log once, with an explicit EventId preserving the exact CodeReference text the
  retired debug_log() calls used to write, so existing dashboards/queries over fds__debuglog
  keep working unchanged.
- Fuchs_DataService/FdsMfr.cs's FdsSqlOptions had the identical double-write hazard (it's hosted
  in the same process per ADR 0010) — the original 2026-09-16 log review's mfr__getSchema/
  fds__getUpdateableRequests deadlock rows came from exactly this class. Fixed the same way.
- fds__debuglog gains LogLevel/Machine/Category/Account/AuthUser/IsDebug columns; the legacy
  fds__admin_logdebug proc is left in place unused, not dropped.
- FdsDebug.DebugLog (Fuchs_DataService's other ~9 call sites) deliberately left on its direct
  DB-write path — no ILogger call sits alongside it there, so no duplication risk today.

See ADR 0024 (supersedes 0023) and Docs/Concepts/error-logging-pipeline.md.

New tests: ErrorLoggingTests (FIS_SQLOptions), FdsSqlOptionsTests, RequestLogScopeMiddlewareTests.
694/694 pass (the 4 PdfPipelineTests failures seen under full-suite parallel runs are a
pre-existing, unrelated PdfSharp global-font-resolver test-isolation flake — they pass both
individually and in most full-suite runs).

Bumps the OCORE submodule to 3137b56 (SQL sink hardening: redaction matches short fragments
as whole identifier segments, per-entry-tolerant serialization, lazy dataSerialized, opt-in
SqlLoggerOptions.IncludeCategory, LogEntry.Category/AuthUser capture).

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

Fuchs_Database/dbo/Tables/fds__debuglog.sql

@@ -4,6 +4,15 @@
     [ExceptionMessage] VARCHAR (MAX) NULL,
     [StackTrace]       VARCHAR (MAX) NULL,
     [Data]             VARCHAR (MAX) NULL,
-    [timestamp]        DATETIME      NULL
+    [timestamp]        DATETIME      NULL,
+    -- Columns below are populated only by rows written through the generic OCORE MultiLogger SQL
+    -- sink (fds__admin_logdebug_ext, see ADR 0024) — every _logger.LogWarning/-Error/-Critical call
+    -- at Warning+, attributed automatically. NULL on rows still written by the legacy, explicit
+    -- fds__admin_logdebug proc call.
+    [LogLevel]         CHAR (1)      NULL,  -- T/D/I/W/E/C, see OCORE.MultiLogger.SqlLoggerProvider.LogLevelChar
+    [Machine]          VARCHAR (255) NULL,  -- Environment.MachineName of the writing process
+    [Category]         VARCHAR (255) NULL,  -- ILogger category, e.g. Fuchs.Controllers.IntranetController
+    [Account]          VARCHAR (100) NULL,  -- reserved by the shared OCORE proc contract; unused by Fuchs
+    [AuthUser]         VARCHAR (100) NULL,  -- fuchs:useraccount_id of the request, when known
+    [IsDebug]          BIT           NULL   -- true when a debugger was attached to the writing process
 );
-