Fonos v0.8.3

Second review-round hardening: complete Apple STT platform gating, a unified agent request path, honest empty-input feedback (#67), an Anthropic capability notice (#69), and a release pipeline that verifies itself before going public.

Fixes

• Apple STT can no longer masquerade as configured off-macOS: both the apple-speech sentinel and real provider: "apple" profiles (the shape first-run actually seeds) are platform-gated in every resolution arm; meetings reject Apple-provider profiles on all platforms (they transcribe over HTTP) with a clear error instead of raw failures.
• Agent requests match the plain LLM path byte-for-byte: one shared request-body builder owns URL, token-param, and temperature rules; Google routes through its /v1beta/openai/ compat endpoint and never gets OpenAI-only parameters. Fixes Google agents failing outright and o-series/nano OpenAI models rejecting agent calls.
• Empty selection no longer flashes "no speech" (#67): a dedicated pill state says "No text selected" / 「未选中文本」, with a debounced OS notification carrying the fuller hint; the Test Run bench shows a distinct status.
• Agent panel discloses the Anthropic limitation (#69 mitigation): a dismissible bilingual notice appears when any resolution path an exchange might take lands on Anthropic (tools are currently dropped there — chat-only), live-refreshing on config changes.
• Setup Doctor hotkey conflicts: key aliases the parser treats as one physical key (return/enter, esc/escape, delete/backspace, arrows, punctuation) now canonicalize together.
• Clipboard restore falls back down the flavor ladder if the richest write fails, instead of leaving the clipboard clobbered.

Release engineering

• Releases are created as drafts by a single prepare-release job (no more matrix race) and published only after an asset-completeness gate proves the DMG, updater tarball, both arches' deb/rpm/AppImage, and a 3-platform latest.json are all present — release-macos.sh now owns the entire notarize → verify → publish path. (That gate correctly blocked this very release twice while an arm64 runner infra failure was retried.)

Full Changelog: v0.8.2...v0.8.3