refactor(main): move plugins, session actions and subtitle generation into assemblies (#327)

* refactor(main): build overlay geometry and pointer interaction in the overlay assembly

Inject Electron's screen (and the stats-window promotion) into the overlay geometry and
visible-overlay interaction runtimes so they load under bun test, then construct both in
createOverlayAssembly together with the overlay visibility composer and the mpv subtitle
suppression handlers. Replace the three regex tests that pinned the moved Linux input and
shape code with behaviour tests on the runtimes.

* refactor(main): move the autoplay-ready gate into the playback assembly

The autoplay-ready gate, its post-warm subtitle prime, the current-media tokenization gate and
managed local subtitle selection all read playback state, and playback signals through the
gate, so createPlaybackAssembly now builds them. The overlay reaches the gate through a getter.

Replace the last four regex guards with behaviour tests: the gate holds the release until the
visible overlay has measured the line and ignores untokenized lines during warmup (playback),
cached autoplay priming never paints raw first and the sidebar media path is tagged only after
prefetch loads (priming runtime), and dashboard mining overrides the Hachidori Anki server only
when the proxy is on (stats server runtime). main-wiring.test.ts is now empty and removed.

* refactor(main): move the plugin host, panel and windows into a plugins assembly

* refactor(main): move session action dispatch and renderer mpv commands into an assembly

createSessionActionsAssembly owns the session action dispatcher, the secondary-subtitle mode cycle, queueing the clipboard's video, and the mpv commands the overlay renderer sends. The runtime option cycle both paths used is now one function.

* refactor(main): move Whisper subtitle generation into an assembly

* refactor(main): resolve subtitle annotation options in a runtime module

The runtime-option-over-config resolution that the texthooker page and the MeCab startup decision share moves out of main.ts into createAnnotationOptions.

* test(main): cover a non-boolean runtime annotation option value

* docs: describe the plugins, session actions and subtitle generation assemblies

Update ownership for overlay geometry and pointer interaction, the autoplay-ready gate, and annotation options; point the overlay priming entry points at their new modules; the main-wiring regex debt is gone.

* build: export MpvClientEvents so declaration emit can name the plugins assembly's return type

docs/architecture/domains.md

@@ -3,7 +3,7 @@
 # Domain Ownership
 
 Status: active
-Last verified: 2026-10-31
+Last verified: 2026-11-01
 Owner: Kyle Yasuda
 Read when: you need to find the owner module for a behavior or test surface
 
@@ -23,19 +23,27 @@ Read when: you need to find the owner module for a behavior or test surface
 - App startup: app-ready sequence, headless known-word refresh, overlay startup prerequisites and
   overlay runtime bootstrap: `src/main/assemblies/startup.ts`
 - Overlay/window state: `src/core/services/overlay-*`, `src/main/overlay-*.ts`
-  Overlay windows, visibility, Linux fullscreen handling, and the overlay-window IPC handlers
-  (modal open/close, pointer interaction, content measurement): `src/main/assemblies/overlay.ts`
+  Overlay windows, visibility, geometry and pointer interaction, Linux fullscreen handling, mpv
+  subtitle suppression while the overlay shows, and the overlay-window IPC handlers (modal
+  open/close, pointer interaction, content measurement): `src/main/assemblies/overlay.ts`
   Overlay-hosted modal openers: `src/main/assemblies/overlay-modals.ts`
 - MPV runtime and protocol: `src/core/services/mpv*.ts`
-  mpv client creation, mpv event wiring, AniSkip, subtitle prefetch, and subtitle sidebar state: `src/main/assemblies/playback.ts`
+  mpv client creation, mpv event wiring, AniSkip, the autoplay-ready gate that releases mpv's
+  startup pause, managed local subtitle selection, subtitle prefetch, and subtitle sidebar state:
+  `src/main/assemblies/playback.ts`
 - Keyboard input outside the renderer (overlay, global and numeric shortcuts, session bindings):
   `src/main/assemblies/shortcuts.ts`
+- Session actions (the dispatcher behind shortcuts, controller buttons, CLI commands and plugin
+  actions), the secondary-subtitle mode cycle, and the overlay renderer's mpv commands:
+  `src/main/assemblies/session-actions.ts`
 - System tray: `src/main/assemblies/tray.ts`
 - Yomitan/Hachidori extension loading, parser runtime deps, and dictionary settings windows:
   `src/main/assemblies/yomitan.ts`
   Windows executable lookup and detached process creation are shared in `src/main/runtime/mpv-process.ts`. The Windows launcher and Jellyfin handlers retain their own playback and connection workflows.
 - Subtitle/token pipeline: `src/core/services/subtitle-*.ts`, `src/core/services/tokenizer*`, `src/core/services/tokenizer/`, `src/subsync/`
   JLPT and frequency annotation lookups: `src/main/jlpt-runtime.ts`, `src/main/frequency-dictionary-runtime.ts`, assembled by `src/main/assemblies/dictionaries.ts`
+  Annotation toggles (a cycled runtime option over its config value): `src/main/runtime/annotation-options.ts`
+  Whisper subtitle generation runtime, modal and IPC: `src/main/assemblies/subtitle-generation.ts`
   Subtitle text filters (`subtitleFilter`): `src/shared/subtitle-text-filter.ts`. Primary text is filtered at its two entry points, live `sub-text` in `mpv-protocol.ts` and parsed cues in `playback.ts`, so every consumer sees the same text and live/cue matching still works. A config change re-reads `sub-text` and re-parses the active track (the prefetch controller's parse key).
 - First-run setup: `src/main/runtime/first-run-setup-*.ts`, assembled by `src/main/assemblies/first-run-setup.ts`
 - Anki workflow: `src/anki-integration/`, `src/core/services/anki-jimaku*.ts`
@@ -55,7 +63,7 @@ Read when: you need to find the owner module for a behavior or test surface
   assembled by `src/main/assemblies/jellyfin.ts`
 - YouTube playback, subtitles, media cache, and in-app browser: `src/core/services/youtube/`,
   `src/main/runtime/youtube-*`, assembled by `src/main/assemblies/youtube.ts`
-- User plugins: `src/core/services/plugins/` (host, `ctx`, `exec`), `src/main/runtime/plugin-panel-runtime.ts` (panel modal), `src/main/runtime/plugin-window-runtime.ts` (plugin windows), `src/renderer/modals/plugin-panel*.ts`; examples in `assets/plugins/`
+- User plugins: `src/core/services/plugins/` (host, `ctx`, `exec`), `src/main/runtime/plugin-panel-runtime.ts` (panel modal), `src/main/runtime/plugin-window-runtime.ts` (plugin windows), assembled by `src/main/assemblies/plugins.ts`; `src/renderer/modals/plugin-panel*.ts`; examples in `assets/plugins/`
 - Window trackers: `src/window-trackers/`
 - Stats HTTP app: `src/core/services/stats-server.ts`, with route groups and shared route support
   in `src/core/services/stats-server/`