fix: invalidate measured widths when terminal geometry changes

[tecfu]

The width cache is keyed by table identity, but auto/percentage widths also depend on the current available terminal width. Re-rendering the same table after a terminal resize could therefore reuse stale column widths. This stores the available width alongside the cached measurement and invalidates the entry when it changes, with a regression test.

[tecfu]

Review: request changes

What's good: resize-invalidation for ordinary tables is correct and the regression test earns its keep — measuredWidths now honestly models what the measurement depended on.

Problem — stream mode loses its shared geometry. The cache lookup becomes cachedEntry = isStream ? undefined : …, so adapter tables re-measure on every render. Probe (3 successive adapter renders, growing row content):

	chunk line-widths
master (7a9f5a3)	7, 7, 7
this branch	7, 27, 7

That jitter is exactly what adapterWidths exists to prevent (documented in the #119 comment this PR leaves in place). #119's characterization test still passes only because its chunks have identical content — it can't see the regression.

Secondary: adapterWidths is now write-only, so npm run lint fails on it (no-unused-vars), i.e. this branch breaks CI's Lint step.

Suggested fix: store availableWidth alongside adapterWidths and invalidate both paths uniformly:

let adapterWidths: { widths: number[], availableWidth: number } | undefined
…
const entry = isStream ? adapterWidths : (config.table ? measuredWidths.get(config.table) : undefined)
const cached = entry && entry.availableWidth === availableWidth ? entry.widths : undefined

plus a stream probe (chunks with different widths, stable viewport) as a real guard.

Matrix otherwise: 0 changed lines; goldens 21/21; vitest 111/111.

Sincerely qwen3.8-flash-next

[tecfu]

Review: request changes — preserve stream geometry while adding resize invalidation

The ordinary table cache fix is correct: cached widths now carry the available terminal width, so a resize causes remeasurement.

The remaining issue is stream/adapter caching. The adapter path has historically used adapterWidths specifically to keep successive streamed renders on a stable geometry. This PR needs to invalidate that shared cache on terminal-width changes without disabling the cache entirely.

Please use the same cache-entry shape for both ordinary and adapter paths, for example storing widths plus availableWidth, compare the cached width against the current available width, and only then reuse it. Add a stream regression with successive records whose natural widths differ; a test with identical rows cannot detect geometry jitter.

That keeps the intended stream behavior while fixing the resize bug.

— GPT-5.6 Luna

[tecfu]

Re-review: changes addressed

The cache implementation now preserves adapter-stream geometry while invalidating it when terminal width changes. The regression now exercises successive stream records with different natural widths.

CI is still running on the new commit; no remaining implementation blocker found.

— GPT-5.6 Luna