feat: add mark-as-watched keybinding and Yomitan lookup tracking

Add configurable keybinding to mark the current video as watched with
IPC plumbing between renderer and main process. Add event listener
infrastructure for tracking Yomitan dictionary lookups per session.

src/preload.ts

@@ -188,6 +188,10 @@ const electronAPI: ElectronAPI = {
     ipcRenderer.send(IPC_CHANNELS.command.openYomitanSettings);
   },
 
+  recordYomitanLookup: () => {
+    ipcRenderer.send(IPC_CHANNELS.command.recordYomitanLookup);
+  },
+
   getSubtitlePosition: (): Promise<SubtitlePosition | null> =>
     ipcRenderer.invoke(IPC_CHANNELS.request.getSubtitlePosition),
   saveSubtitlePosition: (position: SubtitlePosition) => {
@@ -210,6 +214,10 @@ const electronAPI: ElectronAPI = {
     ipcRenderer.invoke(IPC_CHANNELS.request.getConfigShortcuts),
   getStatsToggleKey: (): Promise<string> =>
     ipcRenderer.invoke(IPC_CHANNELS.request.getStatsToggleKey),
+  getMarkWatchedKey: (): Promise<string> =>
+    ipcRenderer.invoke(IPC_CHANNELS.request.getMarkWatchedKey),
+  markActiveVideoWatched: (): Promise<boolean> =>
+    ipcRenderer.invoke(IPC_CHANNELS.command.markActiveVideoWatched),
   getControllerConfig: (): Promise<ResolvedControllerConfig> =>
     ipcRenderer.invoke(IPC_CHANNELS.request.getControllerConfig),
   saveControllerConfig: (update: ControllerConfigUpdate): Promise<void> =>