fix(tui): move usage refresh off event loop

[samzong]

Summary

• stream usage rows into the report accumulator instead of materializing the full event list
• run dashboard sync, usage reports, and skill audit in a background worker; discard stale responses
• reuse the current report when the selected range is already all time

Verification

• make check
• focused worker, stale-response, and aggregation tests
• 4.26 GB cloned production database / 295,444 usage events: output hash unchanged; max RSS reduced from 198.7 MB to 81.7-82.6 MB
• PTY quit while usage refresh was active: 19.66 s on main, 2.90 s on this branch

The JSON CLI still takes roughly 8.5-8.9 s on this dataset. This change removes TUI event-loop blocking and excess materialization; it does not claim query CPU latency is fixed.

[samzong]

@codex review

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 00ea96f8cd

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[codspeed-hq]

Merging this PR will not alter performance

✅ 22 untouched benchmarks
⏩ 2 skipped benchmarks¹

---

_{Comparing feature/release-0.5-ng06 (64f12ba) with main (ebbc570)}

Footnotes

1. 2 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[samzong]

@codex review

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 1fd833e27e

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[samzong]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. 🚀

Reviewed commit: 64f12baffe

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".