feat: git SHA version badge in admin, fix finanzplan caching, drop gitea remote

- AdminShell: shows NEXT_PUBLIC_GIT_SHA in sidebar footer
- Dockerfile + build-pitch-deck.yml: pass --build-arg GIT_SHA at build time
- FinanzplanSlide: fetch with cache:no-store to always show current DB values
- finanzplan routes: Cache-Control: no-store to prevent CDN/proxy staling
- CLAUDE.md: remove dead gitea remote (only origin exists)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/CLAUDE.md

@@ -17,7 +17,7 @@
 ```bash
 # 1. Code auf MacBook bearbeiten (dieses Verzeichnis)
 # 2. Committen und zu BEIDEN Remotes pushen:
-git push origin main && git push gitea main
+git push origin main
 
 # 3. FERTIG! Push auf gitea triggert automatisch:
 #    - Gitea Actions: Tests
@@ -253,7 +253,7 @@ ssh macmini "/usr/local/bin/docker logs -f bp-core-control-pipeline"
 
 ```bash
 # Committen und pushen → Orca deployt automatisch:
-git push origin main && git push gitea main
+git push origin main
 ```
 
 ### Lokale Docker-Befehle (Mac Mini — nur Dev/Tests)
@@ -278,11 +278,11 @@ ssh macmini "/usr/local/bin/docker ps --filter name=bp-core"
 
 ```bash
 # Zu BEIDEN Remotes pushen (PFLICHT!):
-git push origin main && git push gitea main
+git push origin main
 
 # Remotes:
-# origin: lokale Gitea (macmini:3003)
-# gitea:  gitea.meghsakha.com
+
+
 ```
 
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