Release v4.3.1: Version bump and documentation updates

- Updated package.json version to 4.3.1
- Updated marketplace.json version to 4.3.1
- Added v4.3.1 entry to CLAUDE.md version history
- Documented SessionStart hook context injection fix
- Documented hooks architecture consolidation
- Rebuilt all executables with updated version

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

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

.claude-plugin/marketplace.json

@@ -10,7 +10,7 @@
   "plugins": [
     {
       "name": "claude-mem",
-      "version": "4.3.0",
+      "version": "4.3.1",
       "source": "./plugin",
       "description": "Persistent memory system for Claude Code - context compression across sessions"
     }