feat: expand hot-reload to logging, jimaku, subsync, and Anki sub-fields

- Mark logging.level, stats keys, jimaku.*, subsync.*, and granular ankiConnect fields (knownWords, nPlusOne, fields, isLapis, isKiku, behavior) as hot-reloadable
- Refactor classifyConfigHotReloadDiff to path-walk diffing instead of per-key branches
- Wire setLogLevel, invalidateTokenizationCache, refreshSubtitlePrefetch, refreshCurrentSubtitle into hot-reload applied handler
- Exclude ai.* and ankiConnect.ai.* prefixes from config window; hide fields.translation
- Update docs and config.example.jsonc hot-reload annotations

docs-site/public/config.example.jsonc

@@ -46,6 +46,7 @@
   // Logging
   // Controls logging verbosity.
   // Set to debug for full runtime diagnostics.
+  // Hot-reload: logging.level applies live while SubMiner is running.
   // ==========================================
   "logging": {
     "level": "info" // Minimum log level for runtime logging. Values: debug | info | warn | error
@@ -337,6 +338,7 @@
   // ==========================================
   // Auto Subtitle Sync
   // Subsync engine and executable paths.
+  // Hot-reload: subsync changes apply to the next subtitle sync run.
   // ==========================================
   "subsync": {
     "defaultMode": "auto", // Subsync default mode. Values: auto | manual
@@ -470,7 +472,7 @@
   // ==========================================
   // AnkiConnect Integration
   // Automatic Anki updates and media generation options.
-  // Hot-reload: ankiConnect.ai.enabled updates live while SubMiner is running.
+  // Hot-reload: ankiConnect.ai.enabled, knownWords, nPlusOne, fields.word/audio/image/sentence/miscInfo, behavior.autoUpdateNewCards, isLapis.sentenceCardModel, and isKiku.fieldGrouping update live while SubMiner is running.
   // Shared AI provider transport settings are read from top-level ai and typically require restart.
   // Most other AnkiConnect settings still require restart.
   // ==========================================
@@ -550,6 +552,7 @@
   // ==========================================
   // Jimaku
   // Jimaku API configuration and defaults.
+  // Hot-reload: Jimaku changes apply to the next Jimaku request.
   // ==========================================
   "jimaku": {
     "apiBaseUrl": "https://jimaku.cc", // Base URL of the Jimaku subtitle search API.
@@ -560,6 +563,7 @@
   // ==========================================
   // YouTube Playback Settings
   // Defaults for managed subtitle language preferences and YouTube subtitle loading.
+  // Hot-reload: primarySubLanguages applies to the next YouTube subtitle load.
   // ==========================================
   "youtube": {
     "primarySubLanguages": [