docs(bf-2ws): add task summary for acb-index-builder OOMKill fix

- Code fixes completed and committed (b35a2aa, 1b399a1, 7e9d1af)
- Pod currently Pending due to cluster capacity (not CrashLoopBackOff)
- Additional fixes in HEAD not yet deployed
- Verification blocked by cluster resource constraints

notes/bf-2ws-task-summary.md

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+# acb-index-builder OOMKill Fix Task Summary
+
+## Task
+Fix acb-index-builder CrashLoopBackOff (silent crash after web asset copy)
+
+## Root Cause Identified
+**OOMKill caused by N+1 query problems and unbounded database queries:**
+
+1. **fetchBots N+1 query loop**: 10,000+ separate database calls for bot match stats
+2. **fetchSeries N+1 query loop**: 1000+ separate queries for series games  
+3. **fetchChampionshipBracket N+1 query loop**: 500+ separate queries for championship games
+4. **Unbounded queries**: Multiple queries without LIMIT clauses
+
+## Fixes Applied (committed to codebase)
+
+### Commit b35a2aa (DEPLOYED)
+- Fixed N+1 query loop in fetchBots
+- Single batch query for bot match stats
+- Added LIMIT 20000
+
+### Commits 1b399a1, 7e9d1af (code fixed, NOT deployed)
+- Fixed N+1 query loops in fetchSeries and fetchChampionshipBracket
+- Batch queries replacing per-item loops
+- Reduced LIMITs across all queries:
+  - fetchRatingHistory: LIMIT 5000
+  - fetchSeries: LIMIT 1000
+  - fetchSeasons: LIMIT 100
+  - fetchPredictions: LIMIT 1000
+  - fetchMaps: LIMIT 1000
+  - series games batch: LIMIT 10000
+  - championship games batch: LIMIT 500
+  - pair frequency: LIMIT 1000
+
+### main.go panic recovery (lines 165-172)
+- Defer recover() catches panics and logs via slog
+- Prevents silent crashes where stderr is lost
+
+## Current Status
+
+### Deployment State
+- **Deployed image**: ronaldraygun/acb-index-builder:b35a2aa
+- **Code HEAD**: 96d7fb8 (includes ALL fixes)
+- **Gap**: Additional fixes in HEAD not yet deployed
+
+### Cluster Status
+- **Pod**: acb-index-builder-7fc99df58b-5zjpp
+- **Status**: Pending (not CrashLoopBackOff)
+- **Reason**: Cluster overcommitted (94% memory, 98% CPU)
+- **Blocker**: Cannot free resources or deploy new image with read-only access
+
+## Acceptance Criteria Status
+
+| Criteria | Status |
+|----------|--------|
+| acb-index-builder runs through 2+ build cycles | ⏳ Blocked (cluster capacity) |
+| "Build cycle completed" in logs | ⏳ Blocked (pod Pending) |
+| No CrashLoopBackOff | ✅ Not applicable (pod Pending) |
+
+## Conclusion
+
+**Code fixes: ✅ Complete and committed**
+**Deployment: ⏳ Partial (only first fix deployed)**
+**Verification: ⏳ Blocked (cluster capacity constraints)**
+
+The root cause has been identified and fixed in the codebase. Full deployment and verification require:
+1. Building new image with HEAD (96d7fb8)
+2. Freeing cluster resources or scaling cluster
+3. Deploying and monitoring pod for 2+ build cycles