refactor(plugins): remove auto-jimaku example plugin and fix docs

- Remove the auto-jimaku example, now covered by the built-in Jimaku auto-open
- Drop its plugins docs section and changelog bullet
- List the keyboard-only `C` key in Keyboard shortcuts
- Point the configuration reference to Controller support for button defaults

assets/plugins/auto-jimaku/main.js

@@ -1,51 +0,0 @@
-// Opens the Jimaku subtitle search when a file starts without a Japanese subtitle track.
-// It waits a few seconds after the file loads so external subtitles mpv or SubMiner add count.
-
-const DEFAULT_SETTINGS = {
-  // Built-in action to run, e.g. `openTsukihime` or `openSubtitleSelection`.
-  action: 'openJimaku',
-  // Track `lang` codes that count as Japanese. Track titles with "Japanese" or 日本語 count too.
-  languages: ['ja', 'jp', 'jpn'],
-  delayMs: 3_000,
-  // Also check http(s) streams; Jimaku can only search by name, which streams rarely have.
-  streams: false,
-};
-
-const JAPANESE_TITLE = /japanese|日本語/i;
-
-function activate(ctx) {
-  const settings = { ...DEFAULT_SETTINGS, ...ctx.settings };
-  const languages = new Set(settings.languages.map((lang) => lang.toLowerCase()));
-  let cancelCheck = null;
-  let playbackId = null;
-
-  function hasJapaneseSubtitle(trackList) {
-    return trackList.some(
-      (track) =>
-        track?.type === 'sub' &&
-        (languages.has(String(track.lang ?? '').toLowerCase()) ||
-          JAPANESE_TITLE.test(String(track.title ?? ''))),
-    );
-  }
-
-  async function check(media) {
-    cancelCheck = null;
-    const trackList = await ctx.mpv.getProperty('track-list');
-    if (ctx.media.current()?.playbackId !== media.playbackId || !Array.isArray(trackList)) return;
-    if (hasJapaneseSubtitle(trackList)) return;
-    ctx.log.info(`No Japanese subtitles for ${media.path}; running ${settings.action}.`);
-    await ctx.actions.run(settings.action);
-  }
-
-  ctx.media.on('change', (media) => {
-    if (media?.playbackId === playbackId) return;
-    playbackId = media?.playbackId ?? null;
-    cancelCheck?.();
-    cancelCheck = null;
-    if (!media) return;
-    if (!settings.streams && /^[a-z]+:\/\//i.test(media.path)) return;
-    cancelCheck = ctx.after(settings.delayMs, () => check(media));
-  });
-}
-
-module.exports = { activate };

assets/plugins/auto-jimaku/plugin.json

@@ -1,6 +0,0 @@
-{
-  "name": "Auto Jimaku",
-  "version": "1.0.0",
-  "apiVersion": 1,
-  "main": "main.js"
-}