docs: add TSDoc to BasicLlmRequestProcessor, IdentityLlmRequestProcessor, and RequestConfirmationLlmRequestProcessor

[nuthalapativarun]

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Link to Issue or Description of Change

Adds @param and @yields TSDoc comments to the runAsync overrides in three processors that were missing inline documentation:

• BasicLlmRequestProcessor.runAsync — documents invocationContext and llmRequest params
• IdentityLlmRequestProcessor.runAsync — documents invocationContext and llmRequest params
• RequestConfirmationLlmRequestProcessor.runAsync — documents invocationContext param and @yields for the function response events it emits

These are the three processors identified as gaps after PRs #371 and #375 were closed without merging.

Testing Plan

Unit Tests:

• I have added or updated unit tests for my change.
• All unit tests pass locally.

Manual End-to-End (E2E) Tests:
Documentation-only change; no runtime behavior is altered. Verified with npm run build, npm run lint, and npm test — all pass.

Checklist

• Read CONTRIBUTING.md
• Self-reviewed code
• Commented hard-to-understand areas
• Added tests proving fix/feature works
• Unit tests pass locally
• Manually tested end-to-end
• Dependent changes merged/published

[nuthalapativarun]

Closing in favour of the consolidated PR #413, as requested by @kalenkevich. All changes from this PR are included there.