feat(02-03): install @radix-ui/react-tabs, add getClientFullDetail, create Server Actions

- Add shadcn tabs component (src/components/ui/tabs.tsx) backed by @radix-ui/react-tabs
- Extend admin-queries.ts with getClientFullDetail() — fetches client + phases + tasks + deliverables + payments + documents + notes + comments in one call
- Create src/app/admin/clients/[id]/actions.ts with all mutations: addPhase, updatePhaseStatus, addTask, updateTaskStatus, addDeliverable, addDocument, deleteDocument, updatePaymentStatus, updateAcceptedTotal, postAdminComment
- All actions include server-side allowlist validation and revalidatePath
- approved_at immutability enforced by omission in addDeliverable

src/lib/admin-queries.ts

@@ -1,6 +1,25 @@
 import { db } from "@/db";
-import { clients, payments } from "@/db/schema";
-import { eq } from "drizzle-orm";
+import {
+  clients,
+  payments,
+  phases,
+  tasks,
+  deliverables,
+  comments,
+  documents,
+  notes,
+} from "@/db/schema";
+import { eq, inArray, asc } from "drizzle-orm";
+import type {
+  Client,
+  Phase,
+  Task,
+  Deliverable,
+  Payment,
+  Document,
+  Note,
+  Comment,
+} from "@/db/schema";
 
 export type ClientWithPayments = {
   id: string;
@@ -55,3 +74,94 @@ export async function getClientById(id: string) {
     .limit(1);
   return rows[0] ?? null;
 }
+
+// ── ClientFullDetail — used by /admin/clients/[id] workspace ─────────────────
+
+export type ClientFullDetail = {
+  client: Client;
+  phases: Array<Phase & { tasks: Array<Task & { deliverables: Deliverable[] }> }>;
+  payments: Payment[];
+  documents: Document[];
+  notes: Note[];
+  comments: Comment[];
+};
+
+export async function getClientFullDetail(id: string): Promise<ClientFullDetail | null> {
+  const clientRows = await db.select().from(clients).where(eq(clients.id, id)).limit(1);
+  if (clientRows.length === 0) return null;
+  const client = clientRows[0];
+
+  const phasesRows = await db
+    .select()
+    .from(phases)
+    .where(eq(phases.client_id, id))
+    .orderBy(asc(phases.sort_order));
+
+  const phaseIds = phasesRows.map((p) => p.id);
+
+  const tasksRows =
+    phaseIds.length === 0
+      ? []
+      : await db
+          .select()
+          .from(tasks)
+          .where(inArray(tasks.phase_id, phaseIds))
+          .orderBy(asc(tasks.sort_order));
+
+  const taskIds = tasksRows.map((t) => t.id);
+
+  const deliverablesRows =
+    taskIds.length === 0
+      ? []
+      : await db
+          .select()
+          .from(deliverables)
+          .where(inArray(deliverables.task_id, taskIds));
+
+  const paymentsRows = await db
+    .select()
+    .from(payments)
+    .where(eq(payments.client_id, id));
+
+  const documentsRows = await db
+    .select()
+    .from(documents)
+    .where(eq(documents.client_id, id))
+    .orderBy(asc(documents.created_at));
+
+  const notesRows = await db
+    .select()
+    .from(notes)
+    .where(eq(notes.client_id, id))
+    .orderBy(asc(notes.created_at));
+
+  // Fetch all comments for tasks and deliverables belonging to this client
+  const allEntityIds = [...taskIds, ...deliverablesRows.map((d) => d.id)];
+  const commentsRows =
+    allEntityIds.length === 0
+      ? []
+      : await db
+          .select()
+          .from(comments)
+          .where(inArray(comments.entity_id, allEntityIds))
+          .orderBy(asc(comments.created_at));
+
+  const phasesWithTasks = phasesRows.map((phase) => {
+    const phaseTasks = tasksRows
+      .filter((t) => t.phase_id === phase.id)
+      .map((task) => ({
+        ...task,
+        deliverables: deliverablesRows.filter((d) => d.task_id === task.id),
+      }));
+    return { ...phase, tasks: phaseTasks };
+  });
+
+  return {
+    client,
+    phases: phasesWithTasks,
+    payments: paymentsRows,
+    documents: documentsRows,
+    notes: notesRows,
+    comments: commentsRows,
+  };
+}