Add /dashboard route, mark-all-watched on complete, keyboard fixes

- Move dashboard page to app/(pages)/dashboard, redirect / to /dashboard
  for authenticated users, update all nav/breadcrumb/auth hrefs
- Mark all episodes watched when a TV show status is set to "completed"
  (markAllEpisodesWatched skips already-watched episodes)
- Refactor KeyboardProvider to store shortcuts in a ref instead of
  state, eliminating unnecessary re-renders; use react-hotkeys-hook for
  Cmd+K so it works reliably in form inputs
- Fix useRegisterShortcut: re-register on every render (stable ref read)
  with a separate cleanup effect, removing brittle key memoization
- Search page: silently navigate to title detail on import instead of
  showing "Added to library" toast

hooks/use-register-shortcut.ts

@@ -1,14 +1,14 @@
-import { useEffect, useMemo } from "react";
+import { useEffect } from "react";
 import { type ShortcutDef, useKeyboard } from "@/components/keyboard-provider";
 
 export function useRegisterShortcut(id: string, def: ShortcutDef) {
   const { registerShortcut, unregisterShortcut } = useKeyboard();
-  const keysKey = def.keys.join(",");
-  // biome-ignore lint/correctness/useExhaustiveDependencies: stable memoization on keys/description
-  const stableDef = useMemo(() => def, [keysKey]);
 
   useEffect(() => {
-    registerShortcut(id, stableDef);
+    registerShortcut(id, def);
+  });
+
+  useEffect(() => {
     return () => unregisterShortcut(id);
-  }, [id, registerShortcut, unregisterShortcut, stableDef]);
+  }, [id, unregisterShortcut]);
 }