feat(workshop): rebuild install and publish as pages

Replace the stacked install modals (browse -> details -> import review)
with page-based flows so the primary action is always reachable:

- /manage/custom-widgets/workshop browses submissions as a card grid
  with large previews, sitting in a tab next to the installed widgets
- /manage/custom-widgets/workshop/[id] merges the listing, security
  review and source setup onto one page with a sticky install footer
- /manage/custom-widgets/publish/[id] replaces the publish modal
- /manage/workshop redirects; its navbar entry is gone
- the Custom CSS picker collapses from three modals to one

Extract useCustomWidgetImport and ImportReviewContent so the Workshop
page and the file/clipboard dialog share one import pipeline.

Votes now show the viewer's own choice filled Reddit-style, backed by a
new user-votes query, and screenshots get a zoomable lightbox.

Rework the installed list onto ManageCollectionItem: show the widget
description, replace the cryptic "JSX - 2" badge with plain request and
origin facts, and swap the toggle and bare pencil for a status badge,
a labelled Edit button and a menu entry for enable/disable.

Fixes found while reviewing:

- importing could run twice and duplicate a widget; guard on pending and
  succeeded, and return to the installed list instead of the heavy edit
  form
- a background refetch of the submission (window focus, or the
  invalidation a vote triggers) reset the source setup and silently wiped
  part-typed credentials; key the reset on the sources, not the object
- breadcrumbs raised MISSING_MESSAGE for unmapped dynamic segments; fall
  back to the raw segment via t.has
- publishing had no in-flight guard and could post duplicate listings
- tooltips on disabled vote and report controls never fired, making the
  sign-in hint unreachable

packages/custom-widgets/src/test/workshop-translations.spec.ts

@@ -6,17 +6,42 @@ import { describe, expect, test } from "vitest";
 const languageDirectory = resolve(import.meta.dirname, "../../../translation/src/lang");
 
 describe("Workshop navigation translations", () => {
-  test("defines the navbar and breadcrumb label in the source locale", async () => {
+  test("defines the breadcrumb labels for the Custom Widgets sub-routes", async () => {
     const messages = JSON.parse(await readFile(resolve(languageDirectory, "en.json"), "utf8")) as {
       management?: { navbar?: { items?: { workshop?: unknown } } };
-      navigationStructure?: { manage?: { workshop?: { label?: unknown } } };
+      navigationStructure?: {
+        manage?: {
+          workshop?: unknown;
+          "custom-widgets"?: {
+            workshop?: { label?: unknown };
+            publish?: { label?: unknown };
+          };
+        };
+      };
+      customWidget?: { page?: { tabs?: Record<string, unknown> } };
       workshop?: Record<string, unknown>;
     };
-    expect(messages.management?.navbar?.items?.workshop).toBe("Workshop");
-    expect(messages.navigationStructure?.manage?.workshop?.label).toBe("Workshop");
+
+    // The Workshop is reached through the Custom Widgets tabs, not its own navbar entry.
+    expect(messages.management?.navbar?.items?.workshop).toBeUndefined();
+    expect(messages.navigationStructure?.manage?.workshop).toBeUndefined();
+    expect(messages.navigationStructure?.manage?.["custom-widgets"]?.workshop?.label).toBe("Workshop");
+    expect(messages.navigationStructure?.manage?.["custom-widgets"]?.publish?.label).toBe("Publish to Workshop");
+    expect(messages.customWidget?.page?.tabs).toMatchObject({
+      installed: "Installed",
+      workshop: "Workshop",
+      ariaLabel: expect.any(String),
+    });
+
     expect(messages.workshop).toMatchObject({
       communityMember: "Community member",
       outdated: "Outdated",
+      install: "Install",
+      back: expect.any(String),
+      listAriaLabel: expect.any(String),
+      installReviewTitle: expect.any(String),
+      emptyFilteredDescription: expect.any(String),
+      importCssConfirm: expect.any(String),
       reportCount: expect.any(String),
       reportWarning: expect.any(String),
       reportVisibility: expect.any(String),
@@ -31,7 +56,19 @@ describe("Workshop navigation translations", () => {
         inappropriate: expect.any(String),
         other: expect.any(String),
       }),
-      publish: expect.objectContaining({ invalidScreenshot: expect.any(String) }),
+      publish: expect.objectContaining({
+        invalidScreenshot: expect.any(String),
+      }),
     });
   });
+
+  test("drops the message keys that only existed for the stacked install modals", async () => {
+    const messages = JSON.parse(await readFile(resolve(languageDirectory, "en.json"), "utf8")) as {
+      workshop?: Record<string, unknown>;
+    };
+
+    for (const key of ["installDialog", "continueInstall", "confirmInstallTitle", "backToWidget", "inspectCss"]) {
+      expect(messages.workshop).not.toHaveProperty(key);
+    }
+  });
 });