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).

.opencode/skills/openspec-explore/.pi-map.index.md

@@ -0,0 +1,19 @@
+# .opencode/skills/openspec-explore (index)
+dir: .opencode/skills/openspec-explore
+
+## role
+Defines a conversational AI skill that acts as a thinking partner for exploring ideas, investigating problems, and clarifying requirements without implementing code.
+## parent
+index: .opencode/skills/.pi-map.index.md
+map: .opencode/skills/.pi-map.md
+## children
+-
+## files
+- SKILL.md
+## links
+index: .opencode/skills/openspec-explore/.pi-map.index.md
+map: .opencode/skills/openspec-explore/.pi-map.md
+## workflows
+-
+## dirty
+-

.opencode/skills/openspec-explore/.pi-map.md

@@ -0,0 +1,19 @@
+# .opencode/skills/openspec-explore
+dir: .opencode/skills/openspec-explore
+
+index: .opencode/skills/openspec-explore/.pi-map.index.md
+
+## role
+Defines a conversational AI skill that acts as a thinking partner for exploring ideas, investigating problems, and clarifying requirements without implementing code.
+## files
+- SKILL.md | Defines a conversational AI skill/persona for "explore mode" - a thinking partner for exploring ideas, investigating problems, and clarifying requirements without implementing code. | dep: openspec CLI
+## arch
+Markdown-based skill definition using persona/role-prompting pattern with structured behavioral guidelines for non-implementation exploratory conversations.
+## tags
+skill, defines, conversational, persona, explore, mode, thinking, partner
+## symbols
+-
+## workflows
+-
+## dirty
+-