fix: display Codex free quota as 30-day window

[Iamliuxiaozhen]

fix: #141
Related PR:
#142

[graykode]

Security review:

No blocking security findings from this patch. The change only propagates window_minutes as numeric local rate-limit metadata through the existing model/cache/UI path. I did not see any new command execution, path handling, network access, secret exposure, or terminal-control/string injection risk.

Checked:

• Codex JSONL parser and account-level rate-limit filtering
• Codex cache writer/reader
• quota label rendering
• RateLimitInfo construction and serialization call sites

Validation:

• git diff --check origin/main FETCH_HEAD passed
• GitHub check is passing
• Local cargo test was not run because this environment does not have cargo/rustc installed.

[graykode]

Approved from a security-review standpoint. I did not find new command execution, path handling, network access, secret exposure, or terminal-control/string injection risk in this patch.

Scope note: local cargo test was not run in my environment because cargo/rustc are unavailable, but the GitHub check job is passing.

[graykode]

Follow-up validation after local Rust toolchain became available:

• cargo test passed on PR head 3582207
• cargo clippy -- -D warnings passed on PR head 3582207

This supersedes my earlier local-test caveat. My security-review approval still stands.