Show proposals and votes from TaskStream on a project's page

The most voted bug reports and ideas, the link to send one while the
board takes them, and how many want each epic on the roadmap. The mock
API serves a showcase for the catalogue so every section can be seen.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

landing/src/app/core/taskstream.spec.ts

@@ -44,4 +44,17 @@ describe('TaskStream showcase', () => {
     expect(hasContent(showcase)).toBe(true);
     expect(hasContent({ ...showcase, goodFirst: [] })).toBe(false);
   });
+
+  it('counts a board that takes proposals as something to show', () => {
+    const empty = { ...showcase, goodFirst: [] };
+    expect(
+      hasContent({
+        ...empty,
+        proposals: { open: true, path: '/p/WEB/proponer', top: [] },
+      }),
+    ).toBe(true);
+    expect(
+      hasContent({ ...empty, proposals: { open: false, path: null, top: [] } }),
+    ).toBe(false);
+  });
 });