[Blaizzy]

Audio Library currently lets users copy summaries and transcripts but cannot save them as documents. Add ⋯ → Export → PDF / DOCX / TXT to each recording, with every export including the saved summary and verbatim transcript together. Export is available once both sections exist and does not require the original audio file.

Documents include the recording title and date, formatted summary notes, and paginated PDFs. Files are written locally in the background with atomic saves and visible errors. A green checkmark confirmation animates after a successful save and disappears after three seconds, with reduced-motion support.

Validation:

• macOS app build succeeded; signed and reopened the app and confirmed the menu choices.
• All seven focused export tests passed in an isolated XCTest bundle, covering combined content, unavailable sections, DOCX formatting, PDF pagination, Unicode, safe filenames, background writes, and save errors.
• Inspected a generated PDF visually.
• The normal test target is blocked by the existing SystemMonitorIdentityTests.swift import of the unresolved Nativ module.