fix(#338): Disable QuickCaptureWidget in production with Coming Soon

- Show Coming Soon placeholder in production for both widget versions
- Widget available in development mode only
- Added tests verifying environment-based behavior
- Use runtime check for testability (isDevelopment function vs constant)

Refs #338

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/web/src/components/widgets/__tests__/QuickCaptureWidget.test.tsx

@@ -3,7 +3,7 @@
  * Following TDD principles
  */
 
-import { describe, it, expect, vi, beforeEach } from "vitest";
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
 import { render, screen, waitFor } from "@testing-library/react";
 import userEvent from "@testing-library/user-event";
 import { QuickCaptureWidget } from "../QuickCaptureWidget";
@@ -13,6 +13,12 @@ global.fetch = vi.fn() as typeof global.fetch;
 describe("QuickCaptureWidget", (): void => {
   beforeEach((): void => {
     vi.clearAllMocks();
+    // Set development mode by default for existing tests
+    vi.stubEnv("NODE_ENV", "development");
+  });
+
+  afterEach((): void => {
+    vi.unstubAllEnvs();
   });
 
   it("should render input field", (): void => {
@@ -147,4 +153,48 @@ describe("QuickCaptureWidget", (): void => {
       expect(screen.getByText("Test note")).toBeInTheDocument();
     });
   });
+
+  describe("Environment-based behavior", (): void => {
+    it("should show Coming Soon placeholder in production", (): void => {
+      vi.stubEnv("NODE_ENV", "production");
+
+      render(<QuickCaptureWidget id="quick-capture-1" />);
+
+      // Should show Coming Soon badge
+      expect(screen.getByText("Coming Soon")).toBeInTheDocument();
+      // Should show feature name
+      expect(screen.getByText("Quick Capture")).toBeInTheDocument();
+      // Should show description
+      expect(
+        screen.getByText(/Quickly jot down ideas for later organization/i)
+      ).toBeInTheDocument();
+      // Should NOT show the input field
+      expect(screen.queryByRole("textbox")).not.toBeInTheDocument();
+      // Should NOT show the submit button
+      expect(screen.queryByRole("button")).not.toBeInTheDocument();
+    });
+
+    it("should show full widget in development mode", (): void => {
+      vi.stubEnv("NODE_ENV", "development");
+
+      render(<QuickCaptureWidget id="quick-capture-1" />);
+
+      // Should show the input field
+      expect(screen.getByRole("textbox")).toBeInTheDocument();
+      // Should show the submit button
+      expect(screen.getByRole("button", { name: /submit/i })).toBeInTheDocument();
+      // Should NOT show Coming Soon badge
+      expect(screen.queryByText("Coming Soon")).not.toBeInTheDocument();
+    });
+
+    it("should show Coming Soon placeholder in test mode (non-development)", (): void => {
+      vi.stubEnv("NODE_ENV", "test");
+
+      render(<QuickCaptureWidget id="quick-capture-1" />);
+
+      // Test mode is not development, so should show Coming Soon
+      expect(screen.getByText("Coming Soon")).toBeInTheDocument();
+      expect(screen.queryByRole("textbox")).not.toBeInTheDocument();
+    });
+  });
 });