fix(docs): Re-apply M3 fix - Remove duplicate coverage entries (GDD Auto-Repair regression)

CodeRabbit Review #3343936799 M3 fix recurred due to GDD Auto-Repair script
appending coverage values instead of replacing them.

**cost-control.md (lines 8-12):**
- Removed duplicate coverage entries (was 0%, 50%, 50%)
- Now single authoritative value: 50%
- Maintained Coverage Source: auto

**roast.md (lines 8-15):**
- Removed duplicate coverage entries (was 0%, 50%, 50%)
- Now single authoritative value: 50%
- Maintained Coverage Source: auto

✅ All original Review #3343936799 fixes verified intact:
- C1: Perspective API key logging removed (line 54)
- C2: OpenAI API key masked (line 27)
- Extra: YouTube API key masked (line 35)
- M5: OpenAI moderation model parameter added (line 99)
- M6: OpenAI client resilience configs present in 3 services
  - roastGeneratorReal.js (line 18)
  - embeddingsService.js (line 55)
  - modelAvailabilityService.js (line 29)

GDD Auto-Repair script behavior:
- Triggered by CI/CD at 2025-10-16T09:54:51Z
- Appended coverage values instead of replacing
- Caused triple entries: original + 2 appends

**Pattern #10 Candidate**: GDD Auto-Repair Coverage Duplication
- ❌ Issue: Auto-repair appends coverage instead of replacing
- ✅ Fix: Monitor for duplicate entries after CI runs
- 🔄 Temporary: Manual cleanup until auto-repair script fixed
- 📋 Follow-up: Create issue to fix auto-repair append logic

Related: CodeRabbit Review #3343936799 (M3 recurrence), PR #584

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: Eibon7

docs/nodes/cost-control.md

@@ -5,12 +5,9 @@
 **Priority:** Critical
 **Status:** Production
 **Last Updated:** 2025-10-09
-**Coverage:** 0%
+**Coverage:** 50%
 **Coverage Source:** auto
 **Related PRs:** #499
-**Coverage:** 50%
-**Coverage:** 50%
-**Coverage:** 50%
 
 ## Dependencies
 

docs/nodes/roast.md

@@ -5,15 +5,12 @@
 **Priority:** Critical
 **Status:** Production
 **Last Updated:** 2025-10-13
-**Coverage:** 0%
+**Coverage:** 50%
 **Coverage Source:** auto
 **Related PRs:** #499
 **Protected:** true
 **Last Verified:** 2025-10-10
 **Protection Reason:** GDD 2.0 Maintenance Mode - Phase 18 Operational Freeze
-**Coverage:** 50%
-**Coverage:** 50%
-**Coverage:** 50%
 
 ## Dependencies