Panels: colored headers and fixed order

Every WTD panel gets a colored icon in its header (config PANEL_COLORS,
the Scene Manager sub-panels share its green) and the sidebar order is
set with bl_order: Tools, Rename, Scene Manager, Shot Manager, Sanity
Check.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -56,15 +56,17 @@ blender --command extension build --source-dir path/to/wtd-libreflow-addon
 
 ## Where to find the tools
 
-Open the sidebar of the 3D Viewport (**N**) and click the **WTD** tab.
+Open the sidebar of the 3D Viewport (**N**) and click the **WTD** tab. The panels come in this order, each with a colored icon in its header:
 
-| Panel | Editors |
-|---|---|
-| **Sanity Check** | 3D Viewport, Video Sequencer |
-| **Tools** (Get Oid) | 3D Viewport |
-| **Rename** | 3D Viewport, Shader Editor |
-| **Shot Manager** | 3D Viewport |
-| **Scene Manager** (Casting, Loaded, Assetize) | 3D Viewport |
+| Panel | Color | Editors |
+|---|---|---|
+| **Tools** (Get Oid) | blue | 3D Viewport |
+| **Rename** | yellow | 3D Viewport, Shader Editor |
+| **Scene Manager** (Casting, Loaded, Assetize) | green | 3D Viewport |
+| **Shot Manager** | violet | 3D Viewport |
+| **Sanity Check** | orange | 3D Viewport, Video Sequencer |
+
+Panels you drag to another place stay there: a file keeps its own panel order. The colors are `PANEL_COLORS` in the [Configuration](#configuration).
 
 ---
 
@@ -472,6 +474,7 @@ Name formats use Python's `str.format`: `"sq{:04d}"` turns `10` into `sq0010`. `
 | Sanity Check: assets | `REQUIRED_COLLECTIONS`, `MAX_FACE_SIDES`, `CONCAVE_TOLERANCE`, `NON_MANIFOLD_ALLOW_BOUNDARY`, `UV_NEGATIVE_TOLERANCE`, `ALLOWED_MODIFIERS`, `ALLOWED_MODIFIERS_LINEART`, `APPLY_TRANSFORM`, `APPLY_TRANSFORM_TYPES`, `TRANSFORM_TOLERANCE`, `FORBIDDEN_ASSET_OBJECT_TYPES` |
 | Sanity Check: characters | `CHAR_REFERENCE_PATH`, `CHAR_BODY_NAME`, `CHAR_PART_KEYWORDS`, `CHAR_BODY_VERTEX_GROUPS` |
 | Sanity Check: layout | `SET_COLLECTION_PATTERN` |
+| Panels | `PANEL_COLORS` |
 | Sanity Check: panel | `CATEGORY_ORDER`, `MAX_ISSUES_DRAWN` |
 | Rename | `RENAME_SEPARATOR`, `RENAME_PADDING`, `RENAME_SIDES`, `RENAME_TYPE_SUFFIXES` (plus `OBJECT_PREFIXES` / `DATABLOCK_PREFIXES` for *By Type* prefixes) |
 | Shot Manager | `SHOT_VIEWER_RIG_GROUPS`, `SHOT_VIEWER_ASSET_TYPE_GROUPS`, `SHOT_NAME_FORMAT`, `SHOT_NUMBER_STEP`, `SHOT_FRAME_START`, `SHOT_DEFAULT_DURATION`, `SEQUENCE_NAME_FORMAT`, `SHOT_CAMERA_NAME_FORMAT`, `SHOT_CAMERA_RIG_NAME_FORMAT`, `SHOT_CAMERA_RIG_MODES` |