fix(transcription): accept WhatsApp .opus voice notes in file transcription

[juanmartitegui]

Description

Drag-and-dropping a WhatsApp voice note (.opus) onto the file-transcription drop zone shows "Accepted file types…" and rejects the file, even though macOS decodes Ogg Opus natively.

Root cause: MeetingTranscriptionService.supportedFileExtensions is built from AVURLAsset.audiovisualTypes(), but only keeps each UTType's single preferredFilenameExtension. The Ogg audio type (org.xiph.ogg-audio) declares the extension tags ["ogg", "oga", "opus"] with ogg as preferred, so .opus and .oga were dropped from the accepted set while the decoder fully supports them (verified with a real WhatsApp .opus file: AVAudioFile/AVAsset read it fine — mono, 48 kHz, 24 s).

Fix: build the set from every filenameExtension tag of each decodable audio/video UTType instead of just the preferred one, and mention OPUS in the supported-formats copy. No transcoding or special-casing needed — the existing pipeline handles the file once the extension check stops rejecting it. Every previously accepted extension is still accepted (verified: old set ⊆ new set); the set still derives only from what AVFoundation reports as decodable, so subtitles/playlists remain excluded.

Type of Change

• 🐞 Bug fix
• ✨ New feature
• 💥 Breaking change
• 🧹 Chore
• 📝 Documentation update

Related Issue or Discussion

Closes #868

Testing

• Tested on Intel Mac
• Tested on Apple Silicon Mac
• Tested on macOS version: 26 (Darwin 25.5.0)
• Ran linter locally: swiftlint --strict --config .swiftlint.yml Sources (not installed locally — relying on CI)
• Ran formatter locally: swiftformat --config .swiftformat Sources (not installed locally — relying on CI)
• Ran tests locally: added SupportedFileExtensionsTests (regression: .opus/.oga accepted, common formats kept, non-audio types still excluded). Local machine has no full Xcode, so XCTest runs in CI; the exact old-vs-new set logic was verified locally with a standalone Swift script against AVFoundation, and the real WhatsApp .opus file was verified decodable via AVAudioFile/AVAsset.

Screenshots / Video

• No UI/visual changes; screenshots/video are not applicable.

No layout or visual behavior changes. For full transparency, the supported-formats caption/error string constant gains one word:
before — "Supported: WAV, MP3, M4A, OGG, MP4, MOV, and more"
after — "Supported: WAV, MP3, M4A, OGG, OPUS, MP4, MOV, and more"

Notes

UTType.tags[.filenameExtension] also picks up other alternate extensions macOS already decodes (.wave, .bwf, .aif, .mpeg, .m2ts, .3gpp, …), which is strictly more permissive but still bounded by AVURLAsset.audiovisualTypes() — i.e. only formats the OS decoder claims to support.

🤖 Generated with Claude Code

[github-actions]

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[greptile-apps]

Greptile Summary

The PR broadens file-transcription extension detection to include every filename-extension tag exposed by AVFoundation-backed audio and movie UTTypes, allowing WhatsApp .opus voice notes and .oga files through existing validation.

• Adds OPUS to supported-format and drop-error copy.
• Adds regression coverage for Ogg aliases, common formats, and excluded non-media extensions.
• Registers the new tests with the Xcode integration-test target.

Confidence Score: 5/5

The PR appears safe to merge, with no concrete blocking or independently actionable non-blocking issue identified.

The extension set remains bounded to AVFoundation-reported audio and movie UTTypes, both validation paths consume the same set, and the added tests cover the intended aliases and representative regressions.

_{Reviews (1): Last reviewed commit: "fix(transcription): accept .opus/.oga fi..." | Re-trigger Greptile}