fix: support upstream workspace CI partition

scripts/__tests__/run-vitest-stable-shard.test.mjs

@@ -107,9 +107,17 @@ test("general shards retain scripts and route-named suites outside the serialize
   ]) assert.ok(general.selectedGeneralServerSuites.includes(file), `missing configured server suite: ${file}`);
 });
 
-test("shard flags are rejected for the workspaces-b group", () => {
-  const result = dryRun(["--mode", "general", "--group", "general-workspaces-b", "--shard-index", "0", "--shard-count", "3"]);
-  assert.notEqual(result.status, 0, "workspaces-b must not accept shard flags");
+for (const group of ["general-workspaces-b", "general-workspaces-c"]) {
+  test(`shard flags are rejected for the ${group} group`, () => {
+    const result = dryRun(["--mode", "general", "--group", group, "--shard-index", "0", "--shard-count", "3"]);
+    assert.notEqual(result.status, 0, `${group} must not accept shard flags`);
+  });
+}
+
+test("workspaces-c selects only the db project", () => {
+  const selected = dryRunJson(["--mode", "general", "--group", "general-workspaces-c"]);
+  assert.deepEqual(selected.workspaceProjects, ["@paperclipai/db"]);
+  assert.equal(selected.workspacesVitestShard, null);
 });
 
 test("workspace lanes cover every non-server project in the root Vitest configuration", () => {
@@ -118,7 +126,7 @@ test("workspace lanes cover every non-server project in the root Vitest configur
   assert.ok(roots.includes("server"), "expected the explicit root Vitest project list");
   const expected = roots.filter(root => root !== "server")
     .map(root => JSON.parse(readFileSync(path.join(repoRoot, root, "package.json"), "utf8")).name).sort();
-  const actual = ["general-workspaces-a", "general-workspaces-b"]
+  const actual = ["general-workspaces-a", "general-workspaces-b", "general-workspaces-c"]
     .flatMap(group => dryRunJson(["--mode", "general", "--group", group]).workspaceProjects).sort();
   assert.deepEqual(actual, expected, "no configured project may be silently omitted or run twice");
 });