feat: add Ollama provider support for local LLMs

[clawmango0]

Summary

Adds Ollama as a new LLM provider option, enabling CashClaw to use local models. This is ideal for users who want to run LLMs locally without sending data to external APIs.

Changes

Backend (src/)

• config.ts: Add ollama to LLMConfig.provider type, default model llama3.1, make apiKey optional for local Ollama, update isConfigured() to not require apiKey for Ollama
• llm/index.ts: Create dedicated createOllamaProvider() function with Ollama-specific handling (localhost:11434, no auth required)

Frontend (src/ui/)

• pages/setup/LLMStep.tsx: Add Ollama option to setup wizard
• pages/Settings.tsx: Add Ollama option to settings page

Tests (test/)

• llm.test.ts: Add 15 comprehensive tests for Ollama provider

Important: Tool Calling Support

Ollama's tool calling support varies by model:

Model	Tool Calling
llama3.1	✅ Supported
qwen2.5	✅ Supported
mistral	✅ Supported
llama3	❌ Not supported
llama2	❌ Not supported

The provider includes helpful error messages when tool calling isn't supported by the model.

Requirements

• Ollama >= 0.1.20
• A model with tool calling support (llama3.1, qwen2.5, mistral)
• Ollama must be running (ollama serve)

Usage

# 1. Install Ollama
curl -fsSL https://ollama.com/install.sh

# 2. Pull a model with tool support (recommended)
ollama pull llama3.1

# 3. Start Ollama server
ollama serve

# 4. In CashClaw setup, select "OLLAMA" provider
#    - API key is NOT required for local Ollama
#    - Default model: llama3.1

Example Config

{
  "llm": {
    "provider": "ollama",
    "model": "llama3.1",
    "apiKey": ""
  }
}

Testing

All tests pass (22 total):

✓ test/llm.test.ts (15 tests)
✓ test/loop.test.ts (7 tests)

Ollama-specific tests:

• Local base URL (http://localhost:11434)
• No API key required for local instance
• Empty string API key handled correctly
• Custom model configuration (llama3.1, qwen:30b, mistral)
• Tool call parsing from Ollama responses
• Helpful error messages for unsupported tool calling
• Error handling for API failures
• Connection error handling (Ollama not running)

Implementation Notes

1. Dedicated Provider: Unlike OpenAI/OpenRouter which share a provider, Ollama has its own provider function to handle:

   • No authentication required for local instances
   • Different error messages
   • Ollama-specific options in the request body

2. Configuration: The isConfigured() function now properly handles Ollama by not requiring an API key when the provider is "ollama".

3. Tool Calling: CashClaw relies on tool calling for the agent to interact with the marketplace (quote tasks, submit work, etc.). Without tool support, the agent can only do text-based reasoning but cannot execute actions.

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Closes #12