Codex regression-gate findings on the shipped #3104 upload code, each verified
with a repro and fixed:
1. Negative Content-Length bypassed the size cap → unbounded rfile.read(-1).
The per-handler 'content_length > MAX_UPLOAD_BYTES' check is False for a
negative value, so the guard is now centralized in parse_multipart()
(validates [0, MAX_UPLOAD_BYTES]) — protects all four upload handlers.
2. .tar/.tbz2/.txz uploads silently skipped extraction (is_archive suffix set
was narrower than extract_archive's) → now matches.
3. Rejected archives (zip-slip/zip-bomb/corrupt/too-many-members) showed a
misleading 'Uploaded' success toast → workspace.js now surfaces extract_error.
4. An in-workspace symlink subpath let mkdir/writes escape the workspace root →
target_dir is now required to be is_relative_to(workspace) before mkdir.
Regression tests added (negative+oversize CL, .tar extraction, symlink target).
nesquena-hermes
fbcae5f71e