feat(workspaces): scaffold feature

Scaffold the workspaces feature package via pnpm turbo gen feature
(single Workspace entity, getWorkspace use case) and hand-wire the
aggregators: bindAll dispatcher (web-next), core-api app router, and
workspace deps. Release-please registration reverted per the root-only
versioning policy (AGENTS.md, ADR-027 retrofit). Pinned @trpc/server
to the repo-wide 11.16.0 resolution so instanceof TRPCError checks
share one module instance.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016j8z4VHjedXDTjEDNg7qHK

packages/workspaces/src/application/repositories/workspace.repository.interface.ts

@@ -0,0 +1,5 @@
+import type { Workspace } from "../../entities/models/workspace";
+
+export interface IWorkspaceRepository {
+  getWorkspace(id: string): Promise<Workspace | null>;
+}

packages/workspaces/src/application/use-cases/get-workspace.use-case.test.ts

@@ -0,0 +1,31 @@
+import { describe, expect, it } from "vitest";
+import { ZodError } from "zod";
+import { getWorkspaceUseCase } from "@/application/use-cases/get-workspace.use-case";
+import { MockWorkspaceRepository } from "@/infrastructure/repositories/workspace.repository.mock";
+import { WorkspaceNotFoundError } from "@/entities/errors/workspace";
+
+describe("getWorkspaceUseCase", () => {
+  it("returns the seeded workspace by id", async () => {
+    const repo = new MockWorkspaceRepository();
+    const useCase = getWorkspaceUseCase(repo);
+    const result = await useCase({ id: "seed-1" });
+    expect(result.id).toBe("seed-1");
+    expect(result.name).toBeTypeOf("string");
+  });
+
+  it("throws WorkspaceNotFoundError when repository returns null", async () => {
+    const repo = new MockWorkspaceRepository(new Map());
+    const useCase = getWorkspaceUseCase(repo);
+    await expect(useCase({ id: "missing" })).rejects.toBeInstanceOf(
+      WorkspaceNotFoundError,
+    );
+  });
+
+  it("throws ZodError when repository returns malformed data", async () => {
+    const malformedRepo = {
+      getWorkspace: async () => ({ id: "", name: "x" }) as never,
+    };
+    const useCase = getWorkspaceUseCase(malformedRepo);
+    await expect(useCase({ id: "anything" })).rejects.toBeInstanceOf(ZodError);
+  });
+});

packages/workspaces/src/application/use-cases/get-workspace.use-case.ts

@@ -0,0 +1,30 @@
+import { z } from "zod";
+
+import { WorkspaceNotFoundError } from "../../entities/errors/workspace";
+import { workspaceSchema } from "../../entities/models/workspace";
+import type { IWorkspaceRepository } from "../repositories/workspace.repository.interface";
+
+// ── Input ────────────────────────────────────────────────────────────────
+export const getWorkspaceInputSchema = z
+  .object({
+    id: z.string().min(1),
+  })
+  .strict();
+export type GetWorkspaceInput = z.infer<typeof getWorkspaceInputSchema>;
+
+// ── Output ───────────────────────────────────────────────────────────────
+export const getWorkspaceOutputSchema = workspaceSchema;
+export type GetWorkspaceOutput = z.infer<typeof getWorkspaceOutputSchema>;
+
+// ── Use case ─────────────────────────────────────────────────────────────
+export type IGetWorkspaceUseCase = ReturnType<typeof getWorkspaceUseCase>;
+
+export const getWorkspaceUseCase =
+  (workspaceRepository: IWorkspaceRepository) =>
+  async (input: GetWorkspaceInput): Promise<GetWorkspaceOutput> => {
+    const result = await workspaceRepository.getWorkspace(input.id);
+    if (!result) {
+      throw new WorkspaceNotFoundError(`Workspace not found: ${input.id}`);
+    }
+    return getWorkspaceOutputSchema.parse(result);
+  };