Breaking change: openrouter_models.json -> custom_models.json

* Support for Custom URLs and custom models, including locally hosted models such as ollama
* Support for native + openrouter + local models (i.e. dozens of models) means you can start delegating sub-tasks to particular models or work to local models such as localizations or other boring work etc.
* Several tests added
* precommit to also include untracked (new) files
* Logfile auto rollover
* Improved logging

.env.example

@@ -1,6 +1,11 @@
 # Zen MCP Server Environment Configuration
 # Copy this file to .env and fill in your values
 
+# Required: Workspace root directory for file access
+# This should be the HOST path that contains all files Claude might reference
+# Defaults to $HOME for direct usage, auto-configured for Docker
+WORKSPACE_ROOT=/Users/your-username
+
 # API Keys - At least one is required
 #
 # IMPORTANT: Use EITHER OpenRouter OR native APIs (Gemini/OpenAI), not both!
@@ -18,10 +23,13 @@ OPENAI_API_KEY=your_openai_api_key_here
 # If using OpenRouter, comment out the native API keys above
 OPENROUTER_API_KEY=your_openrouter_api_key_here
 
-# Optional: Restrict which models can be used via OpenRouter (recommended for cost control)
-# Example: OPENROUTER_ALLOWED_MODELS=gpt-4,claude-3-opus,mistral-large
-# Leave empty to allow ANY model (not recommended - risk of high costs)
-OPENROUTER_ALLOWED_MODELS=
+# Option 3: Use custom API endpoints for local models (Ollama, vLLM, LM Studio, etc.)
+# IMPORTANT: Since this server ALWAYS runs in Docker, you MUST use host.docker.internal instead of localhost
+# ❌ WRONG: http://localhost:11434/v1 (Docker containers cannot reach localhost)
+# ✅ CORRECT: http://host.docker.internal:11434/v1 (Docker can reach host services)
+CUSTOM_API_URL=http://host.docker.internal:11434/v1  # Ollama example (NOT localhost!)
+CUSTOM_API_KEY=                                      # Empty for Ollama (no auth needed)
+CUSTOM_MODEL_NAME=llama3.2                          # Default model name
 
 # Optional: Default model to use
 # Options: 'auto' (Claude picks best model), 'pro', 'flash', 'o3', 'o3-mini'
@@ -41,10 +49,13 @@ DEFAULT_MODEL=auto
 # Defaults to 'high' if not specified
 DEFAULT_THINKING_MODE_THINKDEEP=high
 
-# Optional: Workspace root directory for file access
-# This should be the HOST path that contains all files Claude might reference
-# Defaults to $HOME for direct usage, auto-configured for Docker
-WORKSPACE_ROOT=/Users/your-username
+# Optional: Custom model configuration file path
+# Override the default location of custom_models.json
+# CUSTOM_MODELS_CONFIG_PATH=/path/to/your/custom_models.json
+
+# Optional: Redis configuration (auto-configured for Docker)
+# The Redis URL for conversation threading - typically managed by docker-compose
+# REDIS_URL=redis://redis:6379/0
 
 # Optional: Logging level (DEBUG, INFO, WARNING, ERROR)
 # DEBUG: Shows detailed operational messages for troubleshooting