feat(stack): create unified agents stack with Tatlock and Webber

Consolidate Tatlock API into new agents stack and add Webber LLM agent
orchestration service. Webber provides autonomous agent execution with
tool use, authenticating via Tatlock API.

Changes:
- Add stacks/agents.yml with Tatlock (port 8000) and Webber (port 8086)
- Remove stacks/tatlock.yml (merged into agents stack)
- Document Webber service in CONTAINERS.md (Redis DB 9)
- Add full Tatlock API documentation to CONTAINERS.md

Config updates (pre-existing):
- core-api: Enable OIDC, add host stats access, simplify model config
- gitea: Migrate from dedicated DB to postgres-shared
- media: Remove GPU reservation from Jellyfin

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

stacks/core-api.yml

@@ -20,6 +20,7 @@ services:
       # Application
       - APP_NAME=Core API
       - DEBUG=false
+      - OIDC_ENABLED=true
 
       # Server
       - HOST=0.0.0.0
@@ -28,22 +29,6 @@ services:
       # Logging
       - LOG_LEVEL=INFO
 
-      # Model Configuration
-      - DEFAULT_MODEL=gemma:7b
-      - LIGHTWEIGHT_MODELS=gemma:2b,gemma:7b
-      - HEAVY_MODELS=mistral:7b,gemma2:9b,mixtral:8x7b
-      - CODE_MODELS=codestral:latest,codegemma:latest
-
-      # Model Aliases (OpenAI → Local)
-      - ALIAS_GPT35=gemma:7b
-      - ALIAS_GPT4=mistral:7b
-      - ALIAS_GPT4_TURBO=mixtral:8x7b
-      - ALIAS_GPT4_CODE=codestral:latest
-
-      # Agent Configuration
-      # Set to "false" to make agent errors explicit (500 errors) instead of silent fallback.
-      - AGENT_FALLBACK_ENABLED=false
-
       # Portainer API
       - PORTAINER_URL=http://192.168.86.149:8001
       - PORTAINER_API_KEY=${PORTAINER_API_KEY}
@@ -69,12 +54,16 @@ services:
       - HOMEASSISTANT_TOKEN=${HOMEASSISTANT_TOKEN}
 
       # AI SYSTEM VARIABLES
-      - OLLAMA_BASE_URL=http://192.168.86.149:11434
-      - OLLAMA_TIMEOUT=300
       - SEARXNG_URL=http://192.168.86.149:8080
+      - QDRANT_HOST=192.168.86.149
+      - QDRANT_PORT=6333
 
       # Python path
       - PYTHONPATH=/app
+
+      - PSUTIL_PROCFS_PATH=/host/proc
+      - HOSTFS_ROOT=/hostfs
+      
     volumes:
       # Data volumes only - no source code
       - /home/jpmschweitzer/docker-data/core-api/logs:/app/logs
@@ -83,9 +72,6 @@ services:
       - /proc:/host/proc:ro
       - /sys:/host/sys:ro
       - /:/hostfs:ro
-    environment:
-      - PSUTIL_PROCFS_PATH=/host/proc
-      - HOSTFS_ROOT=/hostfs
 
     deploy:
       resources: