fix: add API key placeholders for LM Studio and Ollama in OpenClaw and Claude Code

[DeJeune]

What this PR does

Before this PR:

• LM Studio and Ollama clients would fail when trying to use Claude Code agent because the services rejected empty API keys, even though these providers don't require authentication.

After this PR:

• OpenClawService and ClaudeCodeService now assign placeholder API key values for local providers that don't require real API keys (Ollama, LM Studio), allowing these providers to work with Claude Code agent.

Fixes #

Why we need it and why it was done in this way

The following tradeoffs were made:

• Used provider ID as the placeholder value in ClaudeCodeService (matching the pattern in BaseService.validateAgentModels)
• Used a lookup map in OpenClawService to support both provider ID and type-based fallback, with a final fallback to 'no-key-required'

The following alternatives were considered:

• Modifying the SDK itself to skip API key validation for local providers (not feasible, SDK is external)
• Using environment variables to indicate which providers don't need keys (more complex than simple placeholder assignment)

Links to places where the discussion took place:

• https://lmstudio.ai/docs/developer/anthropic-compat
• https://docs.openclaw.ai/providers/ollama
• https://docs.ollama.com/api/anthropic-compatibility

Breaking changes

None.

Special notes for your reviewer

The fix follows the existing pattern established in BaseService.validateAgentModels() which already uses provider ID as a placeholder for keyless providers. The changes are minimal and focused on enabling these providers without affecting other functionality.

Checklist

• PR: The PR description is expressive enough and will help future contributors
• Code: Write code that humans can understand and Keep it simple
• Refactor: You have left the code cleaner than you found it (Boy Scout Rule)
• Upgrade: Impact of this change on upgrade flows was considered and addressed if required
• Documentation: A user-guide update was considered and is present (link) or not required. Check this only when the PR introduces or changes a user-facing feature or behavior.
• Self-review: I have reviewed my own code (e.g., via /gh-pr-review, gh pr diff, or GitHub UI) before requesting review from others

Release note

NONE