Fix OpenAI quota window classification

[JeremyMahieu]

OpenAI has suspended 5h window quotas, this causes the UI to misbehave by displaying the weekly quota in the 5h columns because this is now the "primary" one.

https://www.reddit.com/r/OpenAI/comments/1uuqhmk/if_you_noticed_that_in_codex_you_no_longer_a_see/

What changed

• Preserve the upstream rate-limit window duration when parsing usage.
• Classify five-hour and weekly quota windows by their actual duration instead of by the unstable primary_window and secondary_window positions.
• Keep positional fallback behavior for payloads that do not report a duration.

Why

OpenAI currently returns the seven-day quota as primary_window when the temporary five-hour limit is absent, with secondary_window set to null. The proxy previously assumed that primary_window always meant five hours and consequently displayed the weekly percentage in the five-hour column.

Classifying by limit_window_seconds correctly displays the weekly quota today and will automatically recognize the five-hour window if OpenAI restores it later.

Impact

Quota percentages and reset times are assigned to the correct normalized five-hour or weekly window. Routing continues to consume the same normalized fields.

Validation

• docker compose build multivibe
• git diff --check