fix(desktop): support Turkish huddle transcription

[camelludo]

Summary

• replace the English-only huddle recognizer with Whisper Base multilingual
• add Auto, Turkish, and English transcription language settings
• persist the choice for new huddles and retain legacy settings compatibility
• preserve the current 0.5.14 huddle latency and push-to-talk behavior

Related issue

None found.

Testing

• reproduced the defect with real Turkish audio: the old English-only model produced phonetic gibberish
• verified the new model with real Turkish audio: Evet and Merhaba, bugün hangi fırsatlar ilgimi bekliyor.
• cargo fmt --all
• cargo clippy --workspace --all-targets -- -D warnings
• cargo test --workspace (2445 passed, 15 ignored in the main desktop library; auxiliary suites passed)
• pnpm check
• pnpm typecheck
• pnpm build:e2e
• pnpm exec playwright test tests/e2e/voice-settings.spec.ts --project=smoke (6 passed)

The installed signed Buzz application was not replaced; this remains source-level verification pending review and a signed release.