docs(03-02): complete navigation, history, and breadcrumb status bar plan

- Create 03-02-SUMMARY.md documenting HistoryEntry, navigate_to/back/forward, Tab-cycling, breadcrumb
- Update STATE.md: Phase 3 complete, plan 2/2 done, decisions added, session updated
- Update ROADMAP.md: Phase 3 marked complete, 2/2 plans checked
- Mark requirements NAV-03, NAV-04, NAV-11 complete in REQUIREMENTS.md

.planning/REQUIREMENTS.md

@@ -31,15 +31,15 @@ Requirements for initial release. Each maps to roadmap phases.
 
 - [x] **NAV-01**: User can follow `[[wiki-links]]` to other vault documents
 - [x] **NAV-02**: User can follow standard `[text](path.md)` links to other documents
-- [ ] **NAV-03**: User can navigate back through history stack
-- [ ] **NAV-04**: User can navigate forward after going back
+- [x] **NAV-03**: User can navigate back through history stack
+- [x] **NAV-04**: User can navigate forward after going back
 - [x] **NAV-05**: User can scroll content with j/k, arrows, PgUp/PgDn
 - [x] **NAV-06**: User lands on index.md as the entry point
 - [x] **NAV-07**: User sees graceful error page when a linked file is not found
 - [x] **NAV-08**: User sees keyboard hints in status bar
 - [x] **NAV-09**: App handles terminal resize without breaking layout
 - [x] **NAV-10**: User sees links highlighted inline and can Tab-cycle between them
-- [ ] **NAV-11**: User sees breadcrumb / current location in status bar
+- [x] **NAV-11**: User sees breadcrumb / current location in status bar
 
 ### BBS Aesthetic
 
@@ -122,10 +122,10 @@ Which phases cover which requirements. Updated during roadmap creation.
 | NAV-09 | Phase 2 | Complete |
 | NAV-01 | Phase 3 | Complete |
 | NAV-02 | Phase 3 | Complete |
-| NAV-03 | Phase 3 | Pending |
-| NAV-04 | Phase 3 | Pending |
+| NAV-03 | Phase 3 | Complete |
+| NAV-04 | Phase 3 | Complete |
 | NAV-10 | Phase 3 | Complete |
-| NAV-11 | Phase 3 | Pending |
+| NAV-11 | Phase 3 | Complete |
 | BBS-01 | Phase 4 | Pending |
 | BBS-02 | Phase 4 | Pending |
 | LIVE-01 | Phase 4 | Pending |