chore: gitignore nix results, sqlite DBs, compiled JS

Ignore build artifacts and runtime data that shouldn't be tracked:
- Nix build output symlinks (result, result-*)
- SQLite database files (*.db, *.db-shm, *.db-wal)
- Compiled JS from TypeScript HAL service

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitignore

@@ -51,6 +51,7 @@ Thumbs.db
 # Electron
 apps/machine/dist-electron/
 apps/machine/release/
+apps/machine/src/services/*.js
 
 # devenv
 .devenv/
@@ -61,6 +62,15 @@ apps/machine/release/
 docker/**/data/
 docker/.state/
 
+# Nix build outputs
+result
+result-*
+
+# SQLite runtime databases
+*.db
+*.db-shm
+*.db-wal
+
 # Temporary
 tmp/
 temp/