Harden the seams a project sweep surfaced

A systematic review of the whole codebase (main process, renderer,
IPC/migration/packaging seams) surfaced four real defects; each is
fixed at its root:

- Legacy catalogue drift: the operator's profile still carried 89
  active skills from the removed ~/.agents import era next to the 228
  built-ins. Catalogue sync now mirrors the bundle - actives whose slug
  the bundle does not ship retire (bindings keep resolving via their
  pinned revisions; retired skills leave list_skills and cannot be
  granted anew)
- Broken-bundle guard: staging now refuses a bundle without the
  humanizer skill, so an empty or quarantined resources folder can
  never trigger the mirror pass into retiring a healthy catalogue
- Duplicate agent names: @mentions, DM routing, and task assignment all
  resolve by name, so createAgent and updateAgent renames now reject a
  name already held by an active agent (case-insensitive); the mention
  resolver still refuses to guess between legacy duplicates
- Stale DM titles: agent-to-agent conversation rows titled themselves
  from the frozen creation-time space name, so renames never reached
  the sidebar; direct titles now derive from members' current names

Verified clean in the same sweep: IPC surface (82 channels, handler +
preload + api aligned), per-migration transactions with rollback,
quota-parking month rollover, retry-budget counting, meeting spot
reuse across floor-plan rebuilds.

tests/unit/builtin-skills.test.ts

@@ -86,15 +86,49 @@ describe("built-in skills", () => {
     expect(humanizer?.manifest.description).toContain("AI-generated writing");
 
     const first = h.connection.transaction(() => importStagedSkills(h.skills, h.orgId, staged));
-    expect(first).toMatchObject({ imported: 2, skipped: 0, failures: [] });
+    expect(first).toMatchObject({ imported: 2, skipped: 0, retired: 0, failures: [] });
     const second = h.connection.transaction(() => importStagedSkills(h.skills, h.orgId, staged));
-    expect(second).toMatchObject({ imported: 0, skipped: 2 });
+    expect(second).toMatchObject({ imported: 0, skipped: 2, retired: 0 });
     const slugs = (h.connection.db.prepare("select slug from skill_definitions where org_id = ? order by slug").all(h.orgId) as Array<{ slug: string }>)
       .map((row) => row.slug);
     expect(slugs).toEqual(["engineering-backend-architect", "humanizer"]);
     h.connection.close();
   });
 
+  test("legacy catalogue entries retire so every install mirrors the bundle, while their bindings keep working", () => {
+    const h = harness();
+    const staged = stageBuiltinSkillsLibrary(h.sourceRoot, h.libraryRoot);
+    h.connection.transaction(() => importStagedSkills(h.skills, h.orgId, staged));
+
+    // A relic of the old ~/.agents import: active, not in the bundle, bound.
+    let agentId = "";
+    h.connection.transaction(() => {
+      const now = new Date().toISOString();
+      h.connection.db.prepare(`
+        insert into skill_definitions(id, org_id, slug, name, owner_type, status, created_at)
+        values ('skl_legacy', ?, 'legacy-tool', 'Legacy Tool', 'organization', 'active', ?)
+      `).run(h.orgId, now);
+      h.connection.db.prepare(`
+        insert into skill_revisions(id, skill_id, version_semver, manifest_json, source_type, source_ref, published_at, immutable_checksum)
+        values ('skr_legacy', 'skl_legacy', '1.0.0', '{"name":"Legacy Tool","requiredTools":[]}', 'local_directory', '/old', ?, 'sum')
+      `).run(now);
+      agentId = h.organization.createAgent({
+        orgId: h.orgId, name: "Ada", role: "Engineer", department: "Engineering",
+        modelProviderId: null, modelId: null, budgetCents: 1000, managerAgentId: null,
+      });
+      h.skills.bind({ orgId: h.orgId, agentId, skillId: "skl_legacy", revisionId: "skr_legacy" });
+    });
+
+    const report = h.connection.transaction(() => importStagedSkills(h.skills, h.orgId, staged));
+    expect(report.retired).toBe(1);
+    const legacy = h.connection.db.prepare("select status from skill_definitions where id = 'skl_legacy'").get() as { status: string };
+    expect(legacy.status).toBe("retired");
+    const builtinStatuses = (h.connection.db.prepare("select status from skill_definitions where org_id = ? and id <> 'skl_legacy'").all(h.orgId) as Array<{ status: string }>)
+      .map((row) => row.status);
+    expect(new Set(builtinStatuses)).toEqual(new Set(["active"]));
+    h.connection.close();
+  });
+
   test("every agent's run carries humanizer; hire-time skills join it and oversized grants are named, not overflowed", () => {
     const h = harness();
     // A third, oversized flat skill to prove the compiled-prompt cap.

tests/unit/chat-governance.test.ts

@@ -754,7 +754,13 @@ describe("chat governance", () => {
       });
       employeeId = (connection.db.prepare("select id from employees where org_id = ?").get(orgId) as { id: string }).id;
       organization.createAgent({ orgId, name: "Ada", role: "Reviewer", department: "Engineering", modelProviderId: null, modelId: null, budgetCents: 10000, managerAgentId: null });
-      organization.createAgent({ orgId, name: "Ada", role: "Release lead", department: "Engineering", modelProviderId: null, modelId: null, budgetCents: 10000, managerAgentId: null });
+      // The front door refuses duplicate names outright...
+      expect(() => organization.createAgent({ orgId, name: "ada", role: "Release lead", department: "Engineering", modelProviderId: null, modelId: null, budgetCents: 10000, managerAgentId: null }))
+        .toThrow("already exists");
+      // ...but a legacy database may already carry duplicates; mentions must
+      // still refuse to guess between them.
+      const secondId = organization.createAgent({ orgId, name: "Ada Backup", role: "Release lead", department: "Engineering", modelProviderId: null, modelId: null, budgetCents: 10000, managerAgentId: null });
+      connection.db.prepare("update agents set name = 'Ada' where id = ?").run(secondId);
       spaceId = chat.createSpace({ orgId, spaceType: "project", name: "release", topic: "Release coordination", visibility: "workspace" });
     });
 

tests/unit/profile-identity.test.ts

@@ -62,6 +62,32 @@ describe("identity editing", () => {
     h.connection.close();
   });
 
+  test("rejects renaming or hiring into an existing active agent name", () => {
+    const h = harness();
+    h.connection.transaction(() => {
+      h.organization.createAgent({
+        orgId: h.orgId, name: "Dana Lee", role: "Engineer", department: "Engineering",
+        modelProviderId: null, modelId: null, budgetCents: 1000, managerAgentId: h.agentId,
+      });
+    });
+    // Hiring a second "Dana Lee" (any case) is ambiguous for mentions and DMs.
+    expect(() => h.organization.createAgent({
+      orgId: h.orgId, name: "dana lee", role: "Designer", department: "Design",
+      modelProviderId: null, modelId: null, budgetCents: 1000, managerAgentId: h.agentId,
+    })).toThrow("already exists");
+    // Renaming the CEO onto that name is equally ambiguous.
+    expect(() => h.organization.updateAgent({
+      orgId: h.orgId, agentId: h.agentId, name: "Dana Lee", role: "CEO", title: "CEO",
+      roleLevel: "c_suite", department: "Executive", budgetCents: 25000, modelProviderId: null, modelId: null,
+    })).toThrow("already exists");
+    // Saving without changing the name stays legal.
+    h.connection.transaction(() => h.organization.updateAgent({
+      orgId: h.orgId, agentId: h.agentId, name: "CEO", role: "CEO", title: "CEO",
+      roleLevel: "c_suite", department: "Executive", budgetCents: 25000, modelProviderId: null, modelId: null,
+    }));
+    h.connection.close();
+  });
+
   test("rejects blank names and malformed avatar colors", () => {
     const h = harness();
     const base = {