chore(gitignore): ignore the repo-root uploads spill directory (#6089)

UPLOAD_DIR_SERVER is join(process.cwd(), 'uploads'), so it follows the cwd
rather than a fixed root. Under turbo run test the cwd is apps/sim and that
package's /uploads rule catches it, but running vitest from the repo root
writes ~40 uploads/execution/**/large-value-*.json files to a path nothing
ignored.

Anchored on purpose: an unanchored uploads/ would also match
apps/sim/lib/uploads/ (61 tracked source files) and silently ignore anything
added there later.

Author: waleedlatif1

.gitignore

@@ -102,3 +102,14 @@ i18n.cache
 # Python (apps/pii tests/tooling)
 __pycache__/
 .pytest_cache/
+
+# Local file-upload spill directory. `UPLOAD_DIR_SERVER` is
+# `join(process.cwd(), 'uploads')`, so it follows the cwd rather than a fixed
+# root: under `turbo run test` the cwd is apps/sim and `apps/sim/.gitignore`'s
+# `/uploads` catches it, but running vitest from the repo root drops ~40
+# `uploads/execution/**/large-value-*.json` files here instead.
+#
+# Anchored deliberately. An unanchored `uploads/` would also match
+# `apps/sim/lib/uploads/` — 61 files of tracked source — and silently ignore
+# anything added there later.
+/uploads