docs(24-01): complete rate limiter factory and tiered public endpoint limits plan

- Add 24-01-SUMMARY.md with execution results
- Advance plan counter to 2/2
- Update progress to 50% (1 of 2 plans complete)
- Mark INFR-01 requirement complete
- Add factory pattern and tier decisions to STATE.md

.planning/ROADMAP.md

@@ -87,7 +87,7 @@
 **Plans**: 2 plans
 
 Plans:
-- [ ] 24-01-PLAN.md — Rate limit factory and tiered public endpoint protection
+- [x] 24-01-PLAN.md — Rate limit factory and tiered public endpoint protection
 - [ ] 24-02-PLAN.md — Client-side public access (render-first root, auth prompt, setup/catalog guards)
 
 **UI hint**: yes
@@ -144,7 +144,7 @@ Plans:
 | 21. Item & Catalog Detail Pages | v2.0 | 3/3 | Complete | 2026-04-06 |
 | 22. Add-from-Catalog & Thread Integration | v2.0 | 2/2 | Complete | 2026-04-06 |
 | 23. Manual Entry Fallback | v2.0 | 1/1 | Complete | 2026-04-06 |
-| 24. Public Access & Infrastructure | v2.1 | 0/2 | In progress | - |
+| 24. Public Access & Infrastructure | v2.1 | 1/2 | In Progress|  |
 | 25. Catalog Enrichment & Agent Tools | v2.1 | 0/TBD | Not started | - |
 | 26. Discovery Landing Page | v2.1 | 0/TBD | Not started | - |