docs(planning): update STATE.md with quick task 005 completion

Added quick task 005 to completed quick tasks table:
- Label unlabeled PRs in monthly reports to reduce 'Other' section
- Date: 2026-01-28
- Commit: d6c05ff
- 34 PRs labeled, 16% reduction in 'Other' section

Updated last activity timestamp.

Author: castrojo

.planning/STATE.md

@@ -16,7 +16,7 @@ See: .planning/MILESTONES.md (v1.0 shipped, v1.1 shipped)
 **Phase:** SHIPPED ✅ + Post-Launch Improvements Complete  
 **Plan:** All phases complete (Phase 1: 3/3, Phase 2: 2/2, Phase 3: 0/2 deferred)  
 **Status:** PRODUCTION - In active use with recent improvements  
-**Last activity:** 2026-01-27 - Completed quick task 004: change the blog slugs for the reports blog to have the year and month so that the urls are deterministic
+**Last activity:** 2026-01-28 - Completed quick task 005: Label unlabeled PRs in monthly reports to reduce 'Other' section
 
 **Progress:**
 
@@ -120,6 +120,7 @@ None currently. v1.1 operational and stable.
 | 002 | Continue regenerating the january report with the improvements made to the report structure and subsections | 2026-01-27 | fc9f2ed | [002-continue-regenerating-the-january-report](./quick/002-continue-regenerating-the-january-report/) |
 | 003 | check the update driver versions workflow and see if automation improvements can be made                    | 2026-01-28 | 4678b73 | [003-check-the-update-driver-versions-workflo](./quick/003-check-the-update-driver-versions-workflo/) |
 | 004 | change the blog slugs for the reports blog to have the year and month so that the urls are deterministic    | 2026-01-27 | d795390 | [004-change-the-blog-slugs-for-the-reports-bl](./quick/004-change-the-blog-slugs-for-the-reports-bl/) |
+| 005 | Label unlabeled PRs in monthly reports to reduce 'Other' section                                            | 2026-01-28 | d6c05ff | [005-label-unlabeled-prs-in-monthly-reports-t](./quick/005-label-unlabeled-prs-in-monthly-reports-t/) |
 
 ### Technical Notes