What

The right-side context meter (sidebar) summed cacheHitTokens and cacheMissTokens, which are session-wide running totals, and tried to render them against a 1M ceiling. After ~20 cached turns of a 50k-token context the cumulative cacheHit alone reaches 1M+ and the panel renders something like:

1,500,000 / 1,000,000

…with the bar pegged at 100%. /compact partially patched this by resetting the cumulative counters via \$ctx_breakdown, but the very next model.final started accumulating again, so the fix only held for one frame.

Why

What the meter is supposed to show is the current context size — i.e. prompt_tokens of the most recent API call. That value is already captured per-turn as lastCallCacheHit / lastCallCacheMiss in App.tsx — context-panel.tsx just wasn't using them.

Cumulative totals are still the right choice elsewhere (status bar and settings show cache hit rate, which legitimately wants the session-wide sum), so I left those alone.

How

• context-panel.tsx: read from lastCallCacheHit / lastCallCacheMiss (null-coalesced to 0 since the type allows null for "no call yet").
• App.tsx: on \$ctx_breakdown with logTokens (the post-/compact reset path), also seed lastCall* so the panel reflects the new size immediately instead of waiting for the next model.final.

How to verify

• Run desktop, chat for ~10 turns until the meter would have shown >1M before this fix — meter should now sit at the actual prompt size.
• Run /compact — meter should drop to the post-compact log size immediately, then track real per-turn input thereafter.
• Existing App.test.ts still passes (no test was asserting the broken cumulative behavior).

Checklist

• npm run verify passes locally
• No Co-Authored-By: Claude trailer
• Comments follow CONTRIBUTING.md (removed the now-stale 3-line comment that justified the old subtraction trick)
• No edits to CHANGELOG.md