feat: add root-level tools map with customParameters to AI Config types

[jsonbailey]

Summary

• Adds LDTool interface with name, type?, parameters?, and customParameters? fields
• Adds tools?: { [toolName: string]: LDTool } to LDAICompletionConfig, LDAICompletionConfigDefault, LDAIAgentConfig, and LDAIAgentConfigDefault
• Updates LDAIConfigFlagValue and LDAIConfigUtils to parse and propagate the root-level tools map
• Adds test coverage for tools in both completion and agent configs

Background

The LaunchDarkly backend now includes a root-level tools map (sibling to model) in AI Config flag variations. This is separate from model.parameters.tools[] which is the raw array passable to LLM providers as-is. LLM providers reject unknown properties, so customParameters cannot live inside model.parameters.tools[] — hence the split.

Wire format:

{
  "tools": {
    "web-search-tool": {
      "name": "web-search-tool",
      "type": "function",
      "parameters": { ... },
      "customParameters": { "some-custom-parameter": "some-custom-value" }
    }
  }
}

Note

Supersedes PR #1175 (devin/1773277027-add-tool-instructions-examples) which had the wrong structure (array instead of map, wrong fields key/version/instructions/examples, and targeted main instead of feat/ai-sdk-next-release).

Test plan

• yarn workspace @launchdarkly/server-sdk-ai test — all existing tests pass, 4 new tests for tools map coverage
• yarn workspace @launchdarkly/server-sdk-ai build — no TypeScript errors
• yarn workspace @launchdarkly/server-sdk-ai lint — no lint errors

🤖 Generated with Claude Code

[github-actions]

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[github-actions]

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@launchdarkly/browser size report
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[github-actions]

@launchdarkly/js-client-sdk-common size report
This is the brotli compressed size of the ESM build.
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Uncompressed size: 204305 bytes