feat: chat UX overhaul — GLM local model, icons, layout modes, instant bubbles

- Add GLM-4.7-Flash as default Ollama model (replaces Mistral)
- Fix WRITE_TIMEOUT (15s→120s) and HTMX timeout (5s→120s) for local LLM
- Auto-warmup model on startup in development mode
- Add /api/chat/status endpoint for model readiness polling
- Show "Initializing AI model..." indicator while model loads
- Add user avatar (mdi:account) on chat messages
- Inject company/project/course sprite icons inline in chat responses
- Replace cramped header icons with 4 icon buttons + tooltips
  (Compact, Side panel, Floating, Full screen)
- Add floating/draggable chat mode with smooth drag support
- Chip questions show user bubble instantly and clear input
- Help modal prefills input instead of auto-sending
- User bubble rendered client-side for immediate feedback

static/css/04-interactive/_chat.css

@@ -98,6 +98,32 @@
     flex: 1;
 }
 
+/* Size: Floating — draggable, resizable feel */
+.chat-panel.chat-float {
+    top: 10vh;
+    left: auto;
+    right: 2rem;
+    bottom: auto;
+    width: 420px;
+    max-height: 70vh;
+    border-radius: 8px;
+    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
+    resize: both;
+    overflow: hidden;
+    transition: none;
+}
+
+/* Disable transition during active drag for instant movement */
+.chat-panel.chat-dragging {
+    transition: none !important;
+    user-select: none;
+}
+
+.chat-panel.chat-float .chat-messages {
+    max-height: none;
+    flex: 1;
+}
+
 /* Size: Full width */
 .chat-panel.chat-full {
     top: 0;
@@ -135,46 +161,64 @@
     font-size: 1.1rem;
 }
 
-/* Size controls — 3 discrete toggle icons */
-.chat-size-controls {
+/* Header actions — icon buttons with tooltips */
+.chat-header-actions {
     margin-left: auto;
     display: flex;
-    gap: 2px;
+    align-items: center;
+    gap: 1px;
 }
 
-.chat-size-opt {
+.chat-mode-btn {
     background: none;
     border: none;
-    color: rgba(255,255,255,0.6);
+    color: rgba(255,255,255,0.5);
     cursor: pointer;
-    font-size: 0.85rem;
-    padding: 2px;
+    font-size: 0.95rem;
+    padding: 4px;
     display: flex;
-    border-radius: 3px;
+    align-items: center;
+    justify-content: center;
+    border-radius: 4px;
     transition: all 0.15s;
+    position: relative;
 }
 
-.chat-size-opt:hover,
-.chat-size-opt.active {
+.chat-mode-btn:hover {
     color: #fff;
     background: rgba(255,255,255,0.15);
 }
 
-.chat-help-btn {
-    margin-left: 0;
-    background: none;
-    border: none;
-    color: var(--action-bar-text-muted, rgba(255, 255, 255, 0.85));
-    cursor: pointer;
-    font-size: 1rem;
-    transition: color 0.2s;
-    display: flex;
-    align-items: center;
-    padding: 0;
+.chat-mode-btn.active {
+    color: #fff;
+    background: rgba(255,255,255,0.2);
 }
 
-.chat-help-btn:hover {
+/* Native tooltip via title attr — enhanced with CSS for consistent look */
+.chat-mode-btn[title]:hover::after {
+    content: attr(title);
+    position: absolute;
+    top: calc(100% + 6px);
+    left: 50%;
+    transform: translateX(-50%);
+    background: var(--black-bar, #2b2b2b);
     color: #fff;
+    padding: 4px 8px;
+    border-radius: 4px;
+    font-size: 0.65rem;
+    font-family: 'Source Sans Pro', sans-serif;
+    font-weight: 400;
+    white-space: nowrap;
+    z-index: 1001;
+    pointer-events: none;
+    box-shadow: 0 2px 8px rgba(0,0,0,0.3);
+}
+
+.chat-header-divider {
+    width: 1px;
+    height: 16px;
+    background: rgba(255,255,255,0.25);
+    margin: 0 3px;
 }
 
 /* ==========================================================================
@@ -222,6 +266,10 @@
     margin-top: 2px;
 }
 
+.chat-avatar-user {
+    background: var(--text-light, #999999);
+}
+
 .chat-msg {
     padding: 10px 14px;
     border-radius: 16px;
@@ -293,6 +341,13 @@
    Navigation Links in Chat Messages
    ========================================================================== */
 
+/* Inline sprite icons in chat messages */
+.chat-msg .icon-sprite {
+    vertical-align: middle;
+    margin-right: 2px;
+    border-radius: 3px;
+}
+
 .chat-nav-link {
     color: var(--accent-green, #27ae60);
     text-decoration: none;
@@ -331,6 +386,24 @@
     display: flex;
 }
 
+.chat-typing-dots {
+    display: inline-flex;
+    align-items: center;
+    gap: 4px;
+}
+
+.chat-status-text {
+    font-size: 0.72rem;
+    color: var(--accent-green, #27ae60);
+    font-style: italic;
+    animation: statusPulse 2s ease-in-out infinite;
+}
+
+@keyframes statusPulse {
+    0%, 100% { opacity: 0.6; }
+    50% { opacity: 1; }
+}
+
 .chat-typing-dot {
     width: 5px;
     height: 5px;