fix(search): accept Fireflies data-array responses - #9490

Summary

• Accept Fireflies transcript lists returned as { data: [...] }, which previously marked the provider unavailable after a successful MCP call.
• Use the existing document validation, pagination and partial-coverage handling. Preserve supported envelopes and rejection of malformed canonical fields.

Type of Change

• Bug fix

Testing

• Wrote the regression cases first. Pre-fix CI failed exactly the three new data-array cases: populated pagination, an empty page, and a page containing an invalid row. The other 25 meeting-provider cases passed; that app shard had 19,434 passing tests and 7 skipped.
• Local lint, all 62 audits, all 29 workspace type checks, required generators and the block-registry check passed. Independent test-audit and correctness reviews found no issues.
• Candidate CI passed all 39 jobs, including unit/type, lint, builds, integration, desktop, mobile and browser-extension checks. All 28 meeting-provider cases passed; the app shard passed 19,437 tests with 7 skipped. No local tests were run.

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing (new tests pass the test-audit authoring gate)
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)