fix(sdk): register init.ingest-docs handler and add registry drift guard (#2442)

The ingest-docs workflow called `gsd-sdk query init.ingest-docs` with a
fallback to `init.default` — neither was registered in createRegistry(),
so the workflow proceeded with `{}` and tried to parse project_exists,
planning_exists, has_git, and project_path from empty.

- Add initIngestDocs handler; register dotted + space aliases
- Simplify workflow call; drop broken fallback
- Repo-wide drift guard scans commands/, agents/, get-shit-done/,
  hooks/, bin/, scripts/, docs/ for `gsd-sdk query <cmd>` and fails
  on any reference with no registered handler (file:line citations)
- Unit tests for the new handler

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

sdk/src/query/init.test.ts

@@ -24,6 +24,7 @@ import {
   initNewWorkspace,
   initListWorkspaces,
   initRemoveWorkspace,
+  initIngestDocs,
 } from './init.js';
 
 let tmpDir: string;
@@ -498,3 +499,24 @@ describe('initRemoveWorkspace', () => {
     expect(data.error).toBeDefined();
   });
 });
+
+describe('initIngestDocs', () => {
+  it('returns flat JSON with ingest-docs branching fields', async () => {
+    const result = await initIngestDocs([], tmpDir);
+    const data = result.data as Record<string, unknown>;
+    expect(data.project_exists).toBe(false);
+    expect(data.planning_exists).toBe(true);
+    expect(typeof data.has_git).toBe('boolean');
+    expect(data.project_path).toBe('.planning/PROJECT.md');
+    expect(data.commit_docs).toBeDefined();
+    expect(data.project_root).toBe(tmpDir);
+  });
+
+  it('reports project_exists true when PROJECT.md is present', async () => {
+    await writeFile(join(tmpDir, '.planning', 'PROJECT.md'), '# project');
+    const result = await initIngestDocs([], tmpDir);
+    const data = result.data as Record<string, unknown>;
+    expect(data.project_exists).toBe(true);
+    expect(data.planning_exists).toBe(true);
+  });
+});