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/ssh-key-mounting/.pi-map.md

@@ -0,0 +1,19 @@
+# openspec/changes/ssh-key-mounting
+dir: openspec/changes/ssh-key-mounting
+
+index: openspec/changes/ssh-key-mounting/.pi-map.index.md
+
+## role
+Defines requirements specification for mounting SSH keys into tool instances to enable secure authentication with external services.
+## files
+- .openspec.yaml | Specification document defining requirements for SSH key mounting feature in tool instances
+## arch
+Declarative specification pattern using YAML-based OpenSpec format to document feature requirements separately from implementation.
+## tags
+.openspec, specification, document, defining, requirements, ssh, key, mounting
+## symbols
+-
+## workflows
+-
+## dirty
+-