feat(ui): add model selection UI to LLM Settings tab

- Three dropdowns for Regular Miku, Evil Miku, Japanese Mode models
- GPU availability badges (Both GPUs / NVIDIA Only / AMD Only)
- Refresh Models + Refresh Status buttons
- Load models on tab switch with defensive checks
- Bump cache-busting version for all JS files
- Remove redundant Current Status section

bot/static/js/core.js

@@ -168,6 +168,13 @@ function switchTab(tabId) {
     showTabLoading('tab6');
     loadAutonomousStats().finally(() => hideTabLoading('tab6'));
   }
+  if (tabId === 'tab4') {
+    if (typeof loadAvailableModels === 'function') {
+      loadAvailableModels();
+    } else {
+      console.warn('loadAvailableModels not available yet (servers.js may not be loaded)');
+    }
+  }
   if (tabId === 'tab9') {
     console.log('🧠 Refreshing memory stats for Memories tab');
     showTabLoading('tab9');