chore: remove all gitea remote references; single origin push only

There is only one remote (origin). Removed all occurrences of:
  - git push gitea / git push origin main && git push gitea main
  - "Pushing to gitea (external)" in deploy.sh
  - # gitea: git@gitea.meghsakha.com:... remote comment in docs-src/index.md
  - "Push auf gitea triggert" → "Push auf origin triggert" in docs
  - Clone URL updated to ssh://git@coolify.meghsakha.com:22222/... in
    README.md and CONTRIBUTING.md

Web UI URLs (gitea.meghsakha.com/...) are unchanged — those are still valid.

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

docs-src/development/ci-cd-pipeline.md

@@ -24,7 +24,7 @@ Uebersicht ueber den Deployment-Prozess fuer BreakPilot Compliance.
 │   ├── developer-portal/     (Next.js)                           │
 │   └── docs-src/             (MkDocs)                            │
 │                                                                   │
-│   git push origin main && git push gitea main                   │
+│   git push origin main                   │
 └───────────────────────────────┬─────────────────────────────────┘
                                 │
                                 │ git push
@@ -63,12 +63,12 @@ Uebersicht ueber den Deployment-Prozess fuer BreakPilot Compliance.
 ```bash
 # Code auf MacBook bearbeiten
 # Committen und zu beiden Remotes pushen:
-git push origin main && git push gitea main
+git push origin main
 ```
 
 ### 2. Automatische Tests (Gitea Actions)
 
-Push auf gitea triggert automatisch die CI-Pipeline:
+Push auf origin triggert automatisch die CI-Pipeline:
 
 - **Go Tests:** `ai-compliance-sdk` Unit Tests
 - **Python Tests:** `backend-compliance`, `document-crawler`, `dsms-gateway`