Add complete homelab documentation and configurations

Documentation:
- OpenCode + LiteLLM integration guide
- LiteLLM complete setup with 16 models
- Gitea centralized configuration guide
- Testing procedures and verification
- API keys setup instructions

Configurations:
- OpenCode config pointing to LiteLLM
- Updated LiteLLM config with all models
- Nextcloud docker-compose template

Scripts:
- Gitea setup automation
- OpenCode testing script

Infrastructure:
- Gitea: 192.168.88.200:3000
- LiteLLM: 192.168.88.27:4000
- Nextcloud: 192.168.88.62

opencode/config.json

@@ -0,0 +1,9 @@
+{
+  "apiProvider": "openai",
+  "apiBase": "http://192.168.88.27:4000",
+  "apiKey": "litellm-local-key-change-in-production",
+  "model": "gpt-4o",
+  "timeout": 600,
+  "maxTokens": 4096,
+  "verbose": true
+}