test: expand API and GUI test coverage across all tools

Add ~500 new E2E tests and ~300 new integration tests covering:

- 24 new GUI E2E specs: navigation, responsive layout, keyboard shortcuts,
  tool UI for all 35 non-AI tools, batch/pipeline workflows, settings/RBAC,
  visual regression, accessibility, and performance budgets
- 3 new E2E-Docker specs: batch workflows, advanced pipelines, cross-format
- 1 new adversarial integration test: memory pressure, corrupted files,
  unicode filenames, extreme dimensions, pipeline/batch edge cases
- 29 expanded integration test files: HEIC/HEIF input, large files, parameter
  boundaries, batch processing, format edge cases across all tools
- Cross-format matrix expanded: 641 tests covering every tool x 18 formats
- AI bridge unit tests expanded: lifecycle, tool modules, error propagation
- Unit test gaps filled: analytics, tool-registry, web stores

Also fixes:
- vitest.config.ts: exclude e2e-docs and e2e-landing from Vitest runner
- AI E2E specs: add sidecar health check to skip gracefully when Python
  AI backend is not running instead of timing out

tests/unit/ai/noise-removal.test.ts

@@ -248,5 +248,86 @@ describe("noiseRemoval", () => {
         expect.objectContaining({ onProgress }),
       );
     });
+
+    it("omits onProgress when not provided", async () => {
+      await noiseRemoval(FAKE_INPUT, FAKE_OUTPUT_DIR);
+
+      const options = vi.mocked(runPythonWithProgress).mock.calls[0][2];
+      expect(options.onProgress).toBeUndefined();
+    });
+  });
+
+  describe("timeout calculation", () => {
+    it("uses minimum 300000ms timeout for small images", async () => {
+      await noiseRemoval(FAKE_INPUT, FAKE_OUTPUT_DIR);
+
+      // 800x600 = 0.48 MP, 0.48 * 120000 = 57600 < 300000
+      const options = vi.mocked(runPythonWithProgress).mock.calls[0][2];
+      expect(options.timeout).toBe(300000);
+    });
+
+    it("scales timeout for large images using megapixels * 120000", async () => {
+      vi.mocked(sharp).mockImplementation(
+        () =>
+          ({
+            png: vi.fn().mockReturnThis(),
+            toBuffer: vi.fn().mockResolvedValue(Buffer.from("mock-png-data")),
+            metadata: vi.fn().mockResolvedValue({ width: 4000, height: 3000 }),
+          }) as unknown as ReturnType<typeof sharp>,
+      );
+
+      await noiseRemoval(FAKE_INPUT, FAKE_OUTPUT_DIR);
+
+      // 4000x3000 = 12 MP, 12 * 120000 = 1440000 > 300000
+      const options = vi.mocked(runPythonWithProgress).mock.calls[0][2];
+      expect(options.timeout).toBe(1440000);
+    });
+
+    it("uses metadata from the PNG-converted buffer for timeout", async () => {
+      // The second sharp() call reads metadata from the PNG buffer
+      let callCount = 0;
+      vi.mocked(sharp).mockImplementation(
+        () =>
+          ({
+            png: vi.fn().mockReturnThis(),
+            toBuffer: vi.fn().mockResolvedValue(Buffer.from("mock-png-data")),
+            metadata: vi
+              .fn()
+              .mockResolvedValue(
+                callCount++ === 0 ? { width: 800, height: 600 } : { width: 2000, height: 2000 },
+              ),
+          }) as unknown as ReturnType<typeof sharp>,
+      );
+
+      await noiseRemoval(FAKE_INPUT, FAKE_OUTPUT_DIR);
+
+      // Timeout is based on the metadata call, which returns dimensions
+      const options = vi.mocked(runPythonWithProgress).mock.calls[0][2];
+      expect(options.timeout).toBeGreaterThanOrEqual(300000);
+    });
+  });
+
+  describe("parseStdoutJson error propagation", () => {
+    it("propagates parseStdoutJson errors", async () => {
+      vi.mocked(parseStdoutJson).mockImplementation(() => {
+        throw new Error("No JSON response from Python script");
+      });
+
+      await expect(noiseRemoval(FAKE_INPUT, FAKE_OUTPUT_DIR)).rejects.toThrow(
+        "No JSON response from Python script",
+      );
+    });
+  });
+
+  describe("sharp conversion", () => {
+    it("converts input to PNG and writes to outputDir", async () => {
+      await noiseRemoval(FAKE_INPUT, FAKE_OUTPUT_DIR);
+
+      expect(sharp).toHaveBeenCalledWith(FAKE_INPUT);
+      expect(writeFile).toHaveBeenCalledWith(
+        `${FAKE_OUTPUT_DIR}/input_denoise.png`,
+        Buffer.from("mock-png-data"),
+      );
+    });
   });
 });