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.

tests/canvas-connection-policy.test.ts

@@ -21,4 +21,60 @@ describe("canvas connection policy", () => {
       getCanvasConnectionValidationMessage("compare-incoming-limit"),
     ).toBe("Compare-Nodes erlauben genau zwei eingehende Verbindungen.");
   });
+
+  it("allows text to video-prompt", () => {
+    expect(
+      validateCanvasConnectionPolicy({
+        sourceType: "text",
+        targetType: "video-prompt",
+        targetIncomingCount: 0,
+      }),
+    ).toBeNull();
+  });
+
+  it("allows video-prompt to ai-video", () => {
+    expect(
+      validateCanvasConnectionPolicy({
+        sourceType: "video-prompt",
+        targetType: "ai-video",
+        targetIncomingCount: 0,
+      }),
+    ).toBeNull();
+  });
+
+  it("blocks direct video-prompt to image prompt flow", () => {
+    expect(
+      validateCanvasConnectionPolicy({
+        sourceType: "video-prompt",
+        targetType: "prompt",
+        targetIncomingCount: 0,
+      }),
+    ).toBe("video-prompt-target-invalid");
+  });
+
+  it("blocks ai-video as adjustment source", () => {
+    expect(
+      validateCanvasConnectionPolicy({
+        sourceType: "ai-video",
+        targetType: "curves",
+        targetIncomingCount: 0,
+      }),
+    ).toBe("adjustment-source-invalid");
+  });
+
+  it("blocks ai-video as render source", () => {
+    expect(
+      validateCanvasConnectionPolicy({
+        sourceType: "ai-video",
+        targetType: "render",
+        targetIncomingCount: 0,
+      }),
+    ).toBe("render-source-invalid");
+  });
+
+  it("describes video-only ai-video input", () => {
+    expect(
+      getCanvasConnectionValidationMessage("ai-video-source-invalid"),
+    ).toBe("KI-Video-Ausgabe akzeptiert nur Eingaben von KI-Video.");
+  });
 });