Resolve 47 of 52 LSP diagnostics: module-not-found errors for @mariozechner/pi-coding-agent and typebox, plus cascading implicit-any errors on callback parameters. Both packages are available on npm and provided at runtime by pi.
Add 34 tests (27 unit, 7 integration) using node:test runner: Unit tests: - pickServer(), findRoot(), pathToUri(), uriToPath() - isLspCommand(), listCommands() - formatHover(), formatDefinition(), formatReferences(), formatDiagnostics() Integration tests: - daemon lifecycle (status/stop) on isolated socket - CLI --no-daemon queries (hover, documentSymbol, diagnostics) Supporting changes: - socketPath() honors PI_LSP_SOCKET_PATH env var for test isolation - test fixtures for valid and broken TypeScript files - npm test / test:unit / test:integration scripts
