feat(canvas): add video-prompt node and enhance video generation support

- Introduced a new node type "video-prompt" for AI video generation, including its integration into the canvas command palette and node template picker.
- Updated connection validation to allow connections from text nodes to video-prompt and from video-prompt to ai-video nodes.
- Enhanced error handling and messaging for video generation failures, including specific cases for provider issues.
- Added tests to validate new video-prompt functionality and connection policies.
- Updated localization files to include new labels and prompts for video-prompt and ai-video nodes.

lib/canvas-node-catalog.ts

@@ -98,6 +98,12 @@ export const NODE_CATALOG: readonly NodeCatalogEntry[] = [
     category: "ai-output",
     phase: 1,
   }),
+  entry({
+    type: "video-prompt",
+    label: "KI-Video",
+    category: "ai-output",
+    phase: 1,
+  }),
   entry({
     type: "ai-text",
     label: "KI-Text",
@@ -108,7 +114,7 @@ export const NODE_CATALOG: readonly NodeCatalogEntry[] = [
   }),
   entry({
     type: "ai-video",
-    label: "KI-Video",
+    label: "KI-Video-Ausgabe",
     category: "ai-output",
     phase: 2,
     systemOutput: true,