chore: archive observability-service-registry, track pi-map artifacts

- Archive the completed observability-service-registry SDD change into
  openspec/changes/archive/ (delivered across 5 slices; only
  jellyfin-service-registry remains active).
- Stop ignoring .pi-map.md / .pi-map.index.md so the navigation maps are
  versioned alongside the code, and add the regenerated map pairs repo-wide.

.opencode/commands/.pi-map.index.md

@@ -0,0 +1,22 @@
+# .opencode/commands (index)
+dir: .opencode/commands
+
+## role
+Defines slash-command workflows and assistant personas for an OpenSpec-based development process (explore, propose, apply, archive).
+## parent
+index: .opencode/.pi-map.index.md
+map: .opencode/.pi-map.md
+## children
+-
+## files
+- opsx-apply.md
+- opsx-archive.md
+- opsx-explore.md
+- opsx-propose.md
+## links
+index: .opencode/commands/.pi-map.index.md
+map: .opencode/commands/.pi-map.md
+## workflows
+-
+## dirty
+-

.opencode/commands/.pi-map.md

@@ -0,0 +1,22 @@
+# .opencode/commands
+dir: .opencode/commands
+
+index: .opencode/commands/.pi-map.index.md
+
+## role
+Defines slash-command workflows and assistant personas for an OpenSpec-based development process (explore, propose, apply, archive).
+## files
+- opsx-apply.md | Defines a workflow for implementing tasks from an OpenSpec change in a structured, iterative manner with pause points for blockers and ambiguity. | dep: openspec CLI, AskUserQuestion tool, filesystem access
+- opsx-archive.md | Defines a workflow for archiving completed changes in an experimental openspec-based development process, including validation, spec sync assessment, and user confirmation steps. | dep: openspec CLI, AskUserQuestion tool, Task tool, Skill tool, filesystem (mkdir, mv), tasks.md
+- opsx-explore.md | Defines the explore mode stance for a thinking/discussion assistant that investigates problems and clarifies requirements without implementing code | dep: OpenSpec system (openspec CLI, change artifacts like proposal.md/design.md/tasks.md/spec.md)
+- opsx-propose.md | Defines a workflow for creating a new change with all required planning artifacts (proposal, design, tasks) in a single step using the openspec CLI tool. | dep: openspec CLI, AskUserQuestion tool, TodoWrite tool, file system
+## arch
+Markdown-based declarative templates serving as structured prompts/playbooks that guide an AI assistant through specific operational phases of a spec-driven lifecycle.
+## tags
+opsx, defines, tasks, md, workflow, openspec, openspec cli, askuserquestion tool
+## symbols
+-
+## workflows
+-
+## dirty
+-