feat: v2.1.0 - Selective saving, cleanup command, and SessionEnd hook

New features:
- /learn:analyze now uses signal detection to save only valuable lessons
  - Explicit commands: "ține minte", "remember", "memorează"
  - Stated preferences: "întotdeauna", "always", "never"
  - Repeated corrections (2+ times)
  - Historical references: "cum am discutat", "as we discussed"
- New /learn:cleanup command for memory hygiene
  - Scoring system for entry quality
  - Conservative mode with confirmation
  - Upgrade option to rewrite entries
- SessionEnd hook shows reminder on /exit, /clear, Ctrl+D
- Metadata tracking: source, confidence, reinforced, trigger

Changes:
- analyze.md: Added Pas 3.5 for signal detection
- cleanup.md: New command for reviewing/deleting entries
- hooks.json: Changed from Stop to SessionEnd
- scripts/session-end-reminder.sh: New reminder script
- Templates updated with metadata fields
- Documentation updated for v2.1.0

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -5,6 +5,38 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.1.0] - 2026-01-06
+
+### Added
+- **Selective saving with signal detection**: `/learn:analyze` now only saves lessons with clear signals
+  - Explicit commands: "ține minte", "memorează", "remember", "don't forget"
+  - Stated preferences: "întotdeauna", "niciodată", "always", "never", "from now on"
+  - Repeated corrections: Same issue corrected 2+ times
+  - Historical references: "cum am discutat", "as we discussed"
+- **New `/learn:cleanup` command**: Review and remove low-value entries
+  - Scoring system based on source, confidence, age, and reinforcement
+  - Conservative mode: always confirms before deleting
+  - Upgrade option: rewrite entries to make them useful
+- **Metadata tracking for entries**:
+  - `source`: explicit | inferred | repeated
+  - `confidence`: high | medium | low
+  - `reinforced`: count of times used in subsequent sessions
+  - `trigger`: original phrase that triggered saving
+- **Reinforcement tracking**: Entries are validated when used in subsequent sessions
+
+### Changed
+- `/learn:analyze` output now shows:
+  - Recommended lessons (high signal)
+  - Possible lessons (low signal)
+  - Excluded one-time fixes
+- **Hook changed from Stop to SessionEnd** - reminder shows on `/exit`, `/clear`, `Ctrl+D`
+- Templates updated with new metadata fields
+- Statistics now include Total Reinforcements and Last Cleanup
+
+### Backward Compatibility
+- Entries without metadata are treated as: source=inferred, confidence=medium, reinforced=0
+- Metadata added automatically on first edit or reinforcement
+
 ## [2.0.0] - 2026-01-06
 
 ### Changed (Repository)