feat: Implement mfr truncation fix and enhance invoice handling

- Added a new SQL script to address the "String or binary data would be truncated" error in mfr sync by widening the Note fields in service objects and companies to NVARCHAR(MAX).
- Updated the table types and associated stored procedures to accommodate the changes, ensuring compatibility with existing data.
- Queued a re-sync for previously rejected rows due to truncation issues.
- Created application logins for fuchs_fds and fuchs_web with placeholder passwords for initial setup.
- Introduced functions for invoice backdating and invoice date retrieval to streamline invoice processing.
- Developed a password generation function with customizable parameters for length and character types.
- Added a random number generation function to support password creation.

Fuchs/Observability/FuchsTelemetry.cs

@@ -57,6 +57,9 @@ public static class FuchsTelemetry
     public static readonly Counter<long> BlobBackupCopiesFailed =
         Meter.CreateCounter<long>("fuchs.blobstorage.backupcopies.failed", "{copy}",
             "Number of blob backup-copy attempts that failed.");
+    public static readonly Counter<long> InvoicesBackdated =
+        Meter.CreateCounter<long>("fuchs.invoices.backdated", "{invoice}",
+            "Invoice finalisations with the admin backdate option (ADR 0032), tagged by outcome.");
     public static readonly Counter<long> InvoiceFileBackups =
         Meter.CreateCounter<long>("fuchs.invoice.filebackups", "{backup}",
             "Admin-triggered invoice file backup+clear actions (Do_Process_Admin backupclearinvoicefile), tagged by outcome.");