chore: track all project map and index files

Add generated .pi-map.md and .pi-map.index.md files across the repository
so the project navigation maps are shared and versioned. These artifacts
are maintained by project_map_init/patch/validate and must be kept in
sync with source edits.

Note: .cache/ remains ignored (added in previous commit).

docs/superpowers/specs/.pi-map.md

@@ -0,0 +1,20 @@
+# docs/superpowers/specs
+dir: docs/superpowers/specs
+
+index: docs/superpowers/specs/.pi-map.index.md
+
+## role
+Contains technical design specifications for planned system features, serving as architectural decision records and implementation blueprints for authentication and session management capabilities.
+## files
+- 2026-05-17-auth-oauth-design.md | Design document for implementing OAuth2/OIDC authentication with Authentik, internal JWT access tokens, and database-backed refresh token rotation. | dep: Authentik, JWKS, JWT, database/PostgreSQL, cookies, pytest, mypy, ruff
+- 2026-05-24-session-branch-selection-design.md | Design document for replacing free-text branch input with a dropdown of available branches and adding the ability to create a new local branch at clone time in a session creation UI. | dep: React/TypeScript frontend, Python/FastAPI backend, Git, API client, ToolInstance database model
+## arch
+Markdown-based design documentation following a date-prefixed naming convention, with each spec detailing problem statements, proposed solutions, data models, API contracts, and security considerations for discrete feature increments.
+## tags
+design, 2026, 05, branch, session, document, authentik, jwt
+## symbols
+-
+## workflows
+-
+## dirty
+-