fix(2137): skip worktree isolation when .gitmodules detected (#2144)

* feat(sdk): add typed query foundation and gsd-sdk query (Phase 1)

Add sdk/src/query registry and handlers with tests, GSDQueryError, CLI query wiring, and supporting type/tool-scoping hooks. Update CHANGELOG. Vitest 4 constructor mock fixes in milestone-runner tests.

Made-with: Cursor

* fix(2137): skip worktree isolation when .gitmodules detected

When a project contains git submodules, worktree isolation cannot
correctly handle submodule commits — three separate gaps exist in
worktree setup, executor commit protocol, and merge-back. Rather
than patch each gap individually, detect .gitmodules at phase start
and fall back to sequential execution, which handles submodules
transparently (Option B).

Affected workflows: execute-phase.md, quick.md

---------

Co-authored-by: David Sienkowski <dave@sienkowski.com>

sdk/src/query/utils.ts

@@ -0,0 +1,92 @@
+/**
+ * Utility query handlers — pure SDK implementations of simple commands.
+ *
+ * These handlers are direct TypeScript ports of gsd-tools.cjs functions:
+ * - `generateSlug` ← `cmdGenerateSlug` (commands.cjs lines 38-48)
+ * - `currentTimestamp` ← `cmdCurrentTimestamp` (commands.cjs lines 50-71)
+ *
+ * @example
+ * ```typescript
+ * import { generateSlug, currentTimestamp } from './utils.js';
+ *
+ * const slug = await generateSlug(['My Phase Name'], '/path/to/project');
+ * // { data: { slug: 'my-phase-name' } }
+ *
+ * const ts = await currentTimestamp(['date'], '/path/to/project');
+ * // { data: { timestamp: '2026-04-08' } }
+ * ```
+ */
+
+import { GSDError, ErrorClassification } from '../errors.js';
+
+// ─── Types ──────────────────────────────────────────────────────────────────
+
+/** Structured result returned by all query handlers. */
+export interface QueryResult {
+  data: unknown;
+}
+
+/** Signature for a query handler function. */
+export type QueryHandler = (args: string[], projectDir: string) => Promise<QueryResult>;
+
+// ─── generateSlug ───────────────────────────────────────────────────────────
+
+/**
+ * Converts text into a URL-safe kebab-case slug.
+ *
+ * Port of `cmdGenerateSlug` from `get-shit-done/bin/lib/commands.cjs`.
+ * Algorithm: lowercase, replace non-alphanumeric with hyphens,
+ * strip leading/trailing hyphens, truncate to 60 characters.
+ *
+ * @param args - `args[0]` is the text to slugify
+ * @param _projectDir - Unused (pure function)
+ * @returns Query result with `{ slug: string }`
+ * @throws GSDError with Validation classification if text is missing or empty
+ */
+export const generateSlug: QueryHandler = async (args, _projectDir) => {
+  const text = args[0];
+  if (!text) {
+    throw new GSDError('text required for slug generation', ErrorClassification.Validation);
+  }
+
+  const slug = text
+    .toLowerCase()
+    .replace(/[^a-z0-9]+/g, '-')
+    .replace(/^-+|-+$/g, '')
+    .substring(0, 60);
+
+  return { data: { slug } };
+};
+
+// ─── currentTimestamp ───────────────────────────────────────────────────────
+
+/**
+ * Returns the current timestamp in the requested format.
+ *
+ * Port of `cmdCurrentTimestamp` from `get-shit-done/bin/lib/commands.cjs`.
+ * Formats: `'full'` (ISO 8601), `'date'` (YYYY-MM-DD), `'filename'` (colons replaced).
+ *
+ * @param args - `args[0]` is the format (`'full'` | `'date'` | `'filename'`), defaults to `'full'`
+ * @param _projectDir - Unused (pure function)
+ * @returns Query result with `{ timestamp: string }`
+ */
+export const currentTimestamp: QueryHandler = async (args, _projectDir) => {
+  const format = args[0] || 'full';
+  const now = new Date();
+  let result: string;
+
+  switch (format) {
+    case 'date':
+      result = now.toISOString().split('T')[0];
+      break;
+    case 'filename':
+      result = now.toISOString().replace(/:/g, '-').replace(/\..+/, '');
+      break;
+    case 'full':
+    default:
+      result = now.toISOString();
+      break;
+  }
+
+  return { data: { timestamp: result } };
+};