docs: anchor documentation rules, rebuild index, archive proposal

- REPO_MAP.md: replace Arbeitsregel with 8 binding documentation rules
  (one fact one home, done leaves the working copy, file types, header
  convention, quarterly gardening)
- WORKFLOW.md Dokumentationspflicht and CLAUDE.md aligned to the rules
- docs/README.md index rebuilt for the consolidated state
- H drive docs merged into ops/h-drive-nearline/README.md (scheduled
  task + no-MIR rule added); docs/H_DRIVE_NEARLINE_PULL.md removed
- implemented proposal archived to docs/archive/2026/

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

ops/h-drive-nearline/README.md

@@ -32,6 +32,15 @@ Abschluss zu löschen.
 - `\\192.168.178.58\backups\borg\dumps\latest` → `borg-dumps\latest\`
 - `\\192.168.178.58\backups\git-bundles\gitea` → `git-bundles\gitea\`
 
+Der Windows Scheduled Task `KalliLab H Drive Nearline Pull` laeuft seit
+2026-05-28 taeglich 05:30. Das Script kopiert bewusst **nicht** mit `/MIR` und
+loescht nichts auf H:/; alte Artefakte werden nur nach manueller Sichtpruefung
+entfernt. Aufruf zum Testen:
+
+```powershell
+powershell.exe -NoProfile -ExecutionPolicy Bypass -File G:\Gitea_Clone\homelab-infra\ops\h-drive-nearline\pull-critical-backups.ps1 -WhatIf
+```
+
 Das Script schließt bewusst aus:
 - `unraid-flash-config.tar.gz` (0600 root:root, nicht per SMB zugänglich → Restore aus Hetzner-Borg)
 - Migration-/Cutover-Verzeichnisse (`immich-vectorchord-*`, `pg18-major-*`, `redis8-*` etc.)