fix: build system, version sync, and error logging improvements

[bark1n0]

Changes

• Fix build system: Add typescript as devDependency — tsc command was not found because the package was missing from node_modules
• Fix version mismatch: Sync VERSION constant in types.ts (3.4.18 → 3.4.19) to match package.json
• Fix dependency version: Update mcp-server core dependency from 3.4.18 → 3.4.19 for consistency
• Improve error handling: Add process.stderr.write logging to empty catch blocks in critical code paths:
• session-start.ts — backfill errors
• session-end.ts — awareness and rooms read errors
• check.ts — correction write errors
• smart-remember.ts — conflict scan and consistency check errors
• recall-backend.ts — backend loading errors

Testing

• npm run build — passes ✅
• npm test — 272/272 tests pass ✅

Notes
Previously, errors in these catch blocks were silently swallowed, making debugging difficult. Now they log to stderr without breaking the main flow (all blocks remain non-blocking).