Feature request: convert large pasted text into an attachment/document in the Codex input

Summary

Please consider adding the same kind of paste behavior that ChatGPT has: when the user pastes a large amount of text into the input box, automatically convert it into a compact document/attachment card instead of inserting the entire text directly into the composer.

This would be very useful in Codex because users often paste long logs, build outputs, stack traces, copied terminal output, issue templates, or long prompts.

Current behavior

When a large block of text is pasted into Codex, it appears to stay directly inside the input composer as plain pasted text. This makes the input area hard to read and manage, especially when the pasted content is very long.

Expected behavior

For large pasted text, Codex could automatically create a temporary text document/attachment, similar to ChatGPT's behavior. The composer could show a small attachment card with something like:

• a generated filename, for example pasted-text.txt, logs.txt, or build-output.txt;
• a short preview or token/line count;
• buttons to expand, preview, rename, remove, or convert back to inline text.

Why this matters

• Makes the composer much cleaner when pasting long logs or large code/output snippets.
• Reduces accidental prompt clutter and makes the final message easier to review before sending.
• Improves performance and responsiveness when handling very large pasted text.
• Helps users manage context more safely and intentionally.
• Matches a behavior that already works well in ChatGPT.

Suggested details

• Trigger only above a reasonable size threshold, such as a large character/line count.
• Preserve exact plain-text content, including newlines, indentation, stack traces, and log formatting.
• Allow users to remove the attachment before sending.
• Allow users to preview the pasted document before sending.
• Consider supporting multiple pasted text attachments in one prompt.

This is related to paste/input ergonomics, not to copying/exporting existing Codex conversations.