docs(02-02): complete markdown renderer plan — REND-01 through REND-10 satisfied

- 02-02-SUMMARY.md: documents render_markdown() pipeline, code block borders, GFM table grid, decisions, deviations
- STATE.md: advance to plan 02 done, update decisions log (02-02 entries), resolve REND Widget trait blocker
- ROADMAP.md: mark 02-02 complete (2/3 plans done for Phase 2)

.planning/ROADMAP.md

@@ -45,10 +45,10 @@ Plans:
   3. User lands on index.md when the app starts; when index.md is missing, a readable error page is shown instead of a crash
   4. User can scroll content longer than the terminal with j/k, arrow keys, and PgUp/PgDn
   5. User sees keyboard hints in the status bar, box-drawing borders on panels, and a CGA-era retro color theme; the layout reflows correctly when the terminal is resized
-**Plans:** 3 plans
+**Plans:** 2/3 plans complete
 Plans:
-- [ ] 02-01-PLAN.md — Dependencies, vault file loading, and syntax highlighter
-- [ ] 02-02-PLAN.md — Markdown-to-styled-lines renderer (all constructs)
+- [x] 02-01-PLAN.md — Dependencies, vault file loading, and syntax highlighter
+- [x] 02-02-PLAN.md — Markdown-to-styled-lines renderer (all constructs)
 - [ ] 02-03-PLAN.md — App integration: scrolling, status bar, error screen, startup wiring
 
 ### Phase 3: Navigation and Links
@@ -82,6 +82,6 @@ Phases execute in numeric order: 1 → 2 → 3 → 4
 | Phase | Plans Complete | Status | Completed |
 |-------|----------------|--------|-----------|
 | 1. Safety Foundation | 3/3 | Complete    | 2026-02-28 |
-| 2. Vault Core and Rendering | 0/3 | Not started | - |
+| 2. Vault Core and Rendering | 2/3 | In Progress | - |
 | 3. Navigation and Links | 0/TBD | Not started | - |
 | 4. BBS Polish and Live Content | 0/TBD | Not started | - |