Separate tree nodes into independent panels, remove graph local search, UI improvements

- Split Sources tab: raw/raw_templates, processed/proc_templates each get own panel
- Split Targets tab: led-devices, led-targets, kc-targets, kc-patterns each get own panel
- Remove graph local search — search button and / key open global command palette
- Add graphNavigateToNode for command palette → graph node navigation
- Add tree group expand/collapse animation (max-height + opacity transition)
- Make tree group headers visually distinct (smaller, uppercase, left border on children)
- Make CardSection collapse opt-in via collapsible flag (disabled by default)
- Move filter textbox next to section title (remove margin-left: auto)
- Fix notification bell button vertical centering in test preview
- Fix clipboard copy on non-HTTPS with execCommand fallback
- Add overlay toggle button on picture-based CSS cards
- Add CSPT to graph add-entity picker and global search
- Update all cross-link navigation paths for new panel keys
- Add i18n keys for new tree groups and search groups (en/ru/zh)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/src/wled_controller/static/css/streams.css

@@ -732,11 +732,15 @@ body.pp-filter-dragging .pp-filter-drag-handle {
     display: flex;
     align-items: center;
     gap: 8px;
-    cursor: pointer;
+    cursor: default;
     user-select: none;
     padding: 8px 0;
 }
 
+.cs-header:has(.cs-chevron) {
+    cursor: pointer;
+}
+
 /* Prevent sticky header from clipping cards that lift on hover */
 [data-cs-content] {
     padding-top: 4px;
@@ -783,7 +787,6 @@ body.pp-filter-dragging .pp-filter-drag-handle {
 
 .cs-filter-wrap {
     position: relative;
-    margin-left: auto;
     width: 180px;
     max-width: 40%;
     flex-shrink: 0;