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).

openspec/changes/archive/2026-05-22-cloudflare-tunnel-instances-superseded/specs/.pi-map.md

@@ -0,0 +1,18 @@
+# openspec/changes/archive/2026-05-22-cloudflare-tunnel-instances-superseded/specs
+dir: openspec/changes/archive/2026-05-22-cloudflare-tunnel-instances-superseded/specs
+
+index: openspec/changes/archive/2026-05-22-cloudflare-tunnel-instances-superseded/specs/.pi-map.index.md
+
+## role
+Contains archived specification documents for a Cloudflare tunnel instances feature that was superseded on May 22, 2026.
+## files
+## arch
+Time-based archival directory structure using ISO date prefixes for change tracking, with flat storage of spec files for historical reference of abandoned design proposals.
+## tags
+-
+## symbols
+-
+## workflows
+-
+## dirty
+-