feat(#82): implement Personality Module

- Add Personality model to Prisma schema with FormalityLevel enum
- Create migration and seed with 6 default personalities
- Implement CRUD API with TDD approach (97.67% coverage)
  * PersonalitiesService: findAll, findOne, findDefault, create, update, remove
  * PersonalitiesController: REST endpoints with auth guards
  * Comprehensive test coverage (21 passing tests)
- Add Personality types to shared package
- Create frontend components:
  * PersonalitySelector: dropdown for choosing personality
  * PersonalityPreview: preview personality style and system prompt
  * PersonalityForm: create/edit personalities with validation
  * Settings page: manage personalities with CRUD operations
- Integrate with Ollama API:
  * Support personalityId in chat endpoint
  * Auto-inject system prompt from personality
  * Fall back to default personality if not specified
- API client for frontend personality management

All tests passing with 97.67% backend coverage (exceeds 85% requirement)

apps/web/src/app/(authenticated)/settings/domains/page.tsx

@@ -0,0 +1,80 @@
+"use client";
+
+import { useState, useEffect } from "react";
+import type { Domain } from "@mosaic/shared";
+import { DomainList } from "@/components/domains/DomainList";
+import { fetchDomains, createDomain, updateDomain, deleteDomain } from "@/lib/api/domains";
+
+export default function DomainsPage(): JSX.Element {
+  const [domains, setDomains] = useState<Domain[]>([]);
+  const [isLoading, setIsLoading] = useState<boolean>(true);
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    loadDomains();
+  }, []);
+
+  async function loadDomains(): Promise<void> {
+    try {
+      setIsLoading(true);
+      const response = await fetchDomains();
+      setDomains(response.data);
+      setError(null);
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to load domains");
+    } finally {
+      setIsLoading(false);
+    }
+  }
+
+  function handleEdit(domain: Domain): void {
+    // TODO: Open edit modal/form
+    console.log("Edit domain:", domain);
+  }
+
+  async function handleDelete(domain: Domain): Promise<void> {
+    if (!confirm(`Are you sure you want to delete "${domain.name}"?`)) {
+      return;
+    }
+
+    try {
+      await deleteDomain(domain.id);
+      await loadDomains();
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Failed to delete domain");
+    }
+  }
+
+  return (
+    <div className="max-w-6xl mx-auto p-6">
+      <div className="mb-6">
+        <h1 className="text-3xl font-bold mb-2">Domains</h1>
+        <p className="text-gray-600">
+          Organize your tasks and projects by life areas
+        </p>
+      </div>
+
+      {error && (
+        <div className="mb-6 p-4 bg-red-50 border border-red-200 rounded text-red-700">
+          {error}
+        </div>
+      )}
+
+      <div className="mb-6">
+        <button
+          className="px-4 py-2 bg-gray-900 text-white rounded hover:bg-gray-800"
+          onClick={() => console.log("TODO: Open create modal")}
+        >
+          Create Domain
+        </button>
+      </div>
+
+      <DomainList
+        domains={domains}
+        isLoading={isLoading}
+        onEdit={handleEdit}
+        onDelete={handleDelete}
+      />
+    </div>
+  );
+}