Add Ollama Cloud provider

[ParthSareen]

Summary

• add Ollama Cloud as a built-in OpenAI-compatible provider using OLLAMA_API_KEY
• seed the current Ollama Cloud model catalog and enrich matching entries with models.dev metadata
• add provider documentation, focused request/streaming tests, and applicable cross-provider matrix coverage

Provider contract

• provider ID: ollama-cloud
• endpoint: https://ollama.com/v1
• default model: glm-5.2
• uses OpenAI Completions with Ollama-compatible token, tool, reasoning, and cache-retention behavior

Validation

• npm run check
• Ollama Cloud unit tests: 3 passed
• coding-agent provider test: 1 passed
• git diff --check

Credential-gated live inference tests were not run.