Drop trailing slash on node_modules gitignore pattern

Lane worktrees use symlinks named node_modules pointing at the main
checkout's installed copies. The previous `node_modules/` pattern only
matched directories, so git saw the symlinks as untracked — which in turn
blocked `ade prs create` preflight and forced /shipLane to fall back to
`gh pr create`. Without the slash, the pattern matches both directories
(main checkout) and symlinks (worktrees).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: arul28

.gitignore

@@ -1,6 +1,6 @@
 .DS_Store
 *.pem
-node_modules/
+node_modules
 /.npm-cache
 /apps/desktop/release-stable
 /apps/desktop/.cache