chore: archive 15 completed OpenSpec changes

Move the following audited-and-implemented changes into
openspec/changes/archive/2026-06-12-completed-changes-archive/:

- backend-frontend-refactoring
- config-profile-git-mounts
- config-profile-includes-ui
- config-profile-multi-repo-mounts
- container-monitoring-notifications
- git-mount-url-validation
- home-path-expansion
- mobile-terminal-ux
- mount-specificity-ordering
- notification-center
- persistent-terminal-sessions
- session-list-overhaul
- ssh-key-mounting
- terminal-fullscreen-unified-header
- tool-session-progress-and-updates

Also regenerated .pi-map*.md files for openspec/changes so the
remaining active changes (multi-session-terminal-ux, reorganize-long-files,
working-copies, workspace-first-ui) reflect the new layout.

openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/.pi-map.index.md

@@ -1,19 +1,19 @@
-# openspec/changes/archive/2026-05-23-remove-built-in-tools/specs (index)
-dir: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs
+# archive/2026-05-23-remove-built-in-tools/specs (index)
+dir: archive/2026-05-23-remove-built-in-tools/specs
 
 ## role
-Contains archived specification documents for a planned removal of built-in tools feature, dated May 23, 2026.
+Contains archived specification documents for the removal of built-in tools feature from the project, dated May 23, 2026.
 ## parent
-index: openspec/changes/archive/2026-05-23-remove-built-in-tools/.pi-map.index.md
-map: openspec/changes/archive/2026-05-23-remove-built-in-tools/.pi-map.md
+index: archive/2026-05-23-remove-built-in-tools/.pi-map.index.md
+map: archive/2026-05-23-remove-built-in-tools/.pi-map.md
 ## children
-- openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types
-  index: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.index.md
-  map: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.md
+- archive/2026-05-23-remove-built-in-tools/specs/tool-types
+  index: archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.index.md
+  map: archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.md
 ## files
 ## links
-index: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/.pi-map.index.md
-map: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/.pi-map.md
+index: archive/2026-05-23-remove-built-in-tools/specs/.pi-map.index.md
+map: archive/2026-05-23-remove-built-in-tools/specs/.pi-map.md
 ## workflows
 -
 ## dirty

openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/.pi-map.md

@@ -1,13 +1,13 @@
-# openspec/changes/archive/2026-05-23-remove-built-in-tools/specs
-dir: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs
+# archive/2026-05-23-remove-built-in-tools/specs
+dir: archive/2026-05-23-remove-built-in-tools/specs
 
-index: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/.pi-map.index.md
+index: archive/2026-05-23-remove-built-in-tools/specs/.pi-map.index.md
 
 ## role
-Contains archived specification documents for a planned removal of built-in tools feature, dated May 23, 2026.
+Contains archived specification documents for the removal of built-in tools feature from the project, dated May 23, 2026.
 ## files
 ## arch
-Simple archival storage pattern using date-based directory naming with no active code or architectural patterns.
+N/A (no code files present; directory serves as historical documentation archive for a completed or planned feature removal)
 ## tags
 -
 ## symbols

openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.index.md

@@ -1,18 +1,18 @@
-# openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types (index)
-dir: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types
+# archive/2026-05-23-remove-built-in-tools/specs/tool-types (index)
+dir: archive/2026-05-23-remove-built-in-tools/specs/tool-types
 
 ## role
-Contains archived software specification documents for historical tool type management system changes from May 2026.
+Archive of historical specification for removing built-in tool types from the system
 ## parent
-index: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/.pi-map.index.md
-map: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/.pi-map.md
+index: archive/2026-05-23-remove-built-in-tools/specs/.pi-map.index.md
+map: archive/2026-05-23-remove-built-in-tools/specs/.pi-map.md
 ## children
 -
 ## files
 - spec.md
 ## links
-index: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.index.md
-map: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.md
+index: archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.index.md
+map: archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.md
 ## workflows
 -
 ## dirty

openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.md

@@ -1,14 +1,14 @@
-# openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types
-dir: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types
+# archive/2026-05-23-remove-built-in-tools/specs/tool-types
+dir: archive/2026-05-23-remove-built-in-tools/specs/tool-types
 
-index: openspec/changes/archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.index.md
+index: archive/2026-05-23-remove-built-in-tools/specs/tool-types/.pi-map.index.md
 
 ## role
-Contains archived software specification documents for historical tool type management system changes from May 2026.
+Archive of historical specification for removing built-in tool types from the system
 ## files
 - spec.md | Software specification document defining modified and removed requirements for a tool type management system
 ## arch
-Document-based specification archive using dated directory versioning with markdown specs for tracking removed/modified requirements.
+Document-based specification storage with dated versioning for change tracking
 ## tags
 spec, software, specification, document, defining, modified, removed, requirements
 ## symbols