v12.3.1

## Error Handling & Code Quality

This patch release resolves error handling anti-patterns across the entire codebase (91 files), improving resilience and correctness.

### Bug Fixes

- **OpenRouterAgent**: Restored assistant replies to `conversationHistory` — multi-turn context was lost after method extraction (#2078)
- **ChromaSync**: Fixed cross-type dedup collision where `observation#N`, `session_summary#N`, and `user_prompt#N` could silently drop results
- **Timeline queries**: Fixed logger calls wrapping Error inside an object instead of passing directly
- **FTS migrations**: Preserved non-Error failure details instead of silently dropping them

### Error Handling Improvements

- Replaced 301 error handling anti-patterns across 91 files:
  - Narrowed overly broad try-catch blocks into focused error boundaries
  - Replaced unsafe `error as Error` casts with `instanceof` checks
  - Added structured error logging where catches were previously empty
  - Extracted large try blocks into dedicated helper methods
- **Installer resilience**: Moved filesystem operations (`mkdirSync`) inside try/catch in Cursor, Gemini CLI, Goose MCP, and OpenClaw installers to maintain numeric return-code contracts
- **GeminiCliHooksInstaller**: Install/uninstall paths now catch `readGeminiSettings()` failures instead of throwing past the `0/1` return contract
- **OpenClawInstaller**: Malformed `openclaw.json` now throws instead of silently returning `{}` and potentially wiping user config
- **WindsurfHooksInstaller**: Added null-safe parsing of `hooks.json` with optional chaining
- **McpIntegrations**: Goose YAML updater now throws when claude-mem markers exist but regex replacement fails
- **EnvManager**: Directory setup and existing-file reads are now wrapped in structured error logging
- **WorktreeAdoption**: `adoptedSqliteIds` mutation delayed until SQL update succeeds
- **Import script**: Guard against malformed timestamps before `toISOString()`
- **Runtime CLI**: Guard `response.json()` parsing with controlled error output

### Documentation

- Added README for Docker claude-mem harness