refactor: extract core-api to standalone repository

Core-API service moved to git.schweitz.net/jpmschweitzer/core-api
- Source code removed from this repository
- Stack file updated to use container image from Gitea registry
- Documentation updated with external service reference
- Removed obsolete docs/services/core-api.md (docs now in core-api repo)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docs/EXTERNAL_SERVICES.md

@@ -36,6 +36,37 @@ To make changes:
 
 ---
 
+## Core-API
+
+**Repository:** https://git.schweitz.net/jpmschweitzer/core-api
+**Container Image:** `git.schweitz.net/jpmschweitzer/core-api:latest`
+**Stack File:** `stacks/core-api.yml` (remains in portainer-core)
+
+### Overview
+Core-API provides infrastructure orchestration and OpenAI-compatible API endpoints:
+- Infrastructure management (Portainer, NPM, Uptime Kuma integration)
+- Web scraping tools
+- AI metrics proxy
+- Service health monitoring
+
+### Deployment
+- Container image built via Gitea Actions on release
+- Stack file in portainer-core defines volumes, environment, and network
+- Watchtower monitors for image updates
+
+### Development
+To make changes:
+1. Clone: `git clone gitea:jpmschweitzer/core-api.git`
+2. Make changes
+3. Create a release in Gitea to trigger build
+4. Watchtower will auto-update the running container
+
+### API
+- Health: `http://core-api:8083/health/full`
+- Docs: `http://core-api:8083/docs`
+
+---
+
 ## Tatlock
 
 **Repository:** https://git.schweitz.net/jpmschweitzer/tatlock
@@ -49,5 +80,4 @@ Tatlock is a separate project maintained in its own repository.
 ## Future Migrations
 
 The following services are planned for extraction:
-- **core-api** - Infrastructure management API
 - **library-desk** - Knowledge management and consolidation service