Fix for #7459
## What
Since codex errors out for unsupported images, stop attempting to
base64/attach them and instead emit a clear placeholder when the file
isn’t a supported image MIME.
## Why
Local uploads for unsupported formats (e.g., SVG/GIF/etc.) were
dead-ending after decode failures because of the 400 retry loop. Users
now get an explicit “cannot attach … unsupported image format …”
response.
## How
Replace the fallback read/encode path with MIME detection that bails out
for non-image or unsupported image types, returning a consistent
placeholder. Unreadable and invalid images still produce their existing
error placeholders.
Title: Improve rollout session initialization error messages
Issue: https://github.com/openai/codex/issues/7283
What: add targeted mapping for rollout/session initialization errors so
users get actionable messages when Codex cannot access session files.
Why: session creation previously returned a generic internal error,
hiding permissions/FS issues and making support harder.
How:
- Added rollout::error::map_session_init_error to translate the more
common io::Error kinds into user-facing hints (permission, missing dir,
file blocking, corruption). Others are passed through directly with
`CodexErr::Fatal`.
- Reused the mapper in Codex session creation to preserve root causes
instead of returning InternalAgentDied.
Job ChongandGitHub