Simplify screenshot diff output

[thymikee]

Summary

Remove retired screenshot-diff analysis while retaining the released pixel and structured region contracts.

The optional ocr and nonTextDeltas fields remain in the TypeScript result contract as deprecated compatibility fields, but the analyzers no longer run and the fields are not emitted. Human output remains compact; no schema migration is required.

Validation

• VITEST_MAX_WORKERS=1 pnpm check:affected --base origin/main --run
• Live iOS simulator evidence against Agent Device Tester: captured a baseline, toggled Lab online, then ran pnpm ad diff screenshot with JSON output. It returned the primary toggle region at x=306 y=327 60x24, 1,310 changed pixels in that region, and 2,019 changed pixels total (0.57%). The retired optional analysis fields were absent.

[github-actions]

PR Preview Action v1.8.1
Preview removed because the pull request was closed.
2026-07-30 12:43 UTC

[github-actions]

Size Report

Metric	Base	Current	Diff
JS raw	1.88 MB	1.87 MB	-11.7 kB
JS gzip	605.4 kB	601.6 kB	-3.9 kB
npm tarball	724.1 kB	720.2 kB	-3.8 kB
npm unpacked	2.53 MB	2.52 MB	-11.7 kB

Startup median (7 runs, lower is better):

Scenario	Base	Current	Diff
CLI --version	28.6 ms	28.8 ms	+0.2 ms
CLI --help	60.1 ms	59.6 ms	-0.5 ms

Top changed chunks:

Chunk	Raw diff	Gzip diff
dist/src/runtime.js	-8.5 kB	-2.8 kB
dist/src/recording-export-quality.js	-2.8 kB	-929 B
dist/src/registry.js	0 B	-5 B
dist/src/context.js	0 B	-2 B
dist/src/apps.js	0 B	-2 B

[thymikee]

Exact head dcf11e8 is not ready because the simplified structured output silently removes shipped API fields. diff screenshot --json and the public runtime result directly expose ScreenshotDiffResult; this patch removes ocr, nonTextDeltas, and region fields including densityPercentage, shape, size, location, colors/luminance, and dominantChange. These fields landed in commit 4b7ee246, which is contained in released tags v0.18.1 through v0.20.3, so they require preservation or an explicit compatibility/versioned migration. Updating tests to stop asserting them does not migrate consumers. The reduced human text is coherent and CI is green, but structured JSON/Node compatibility must be addressed. Also add reproducible live diff screenshot device evidence (command plus artifact); the PR\x27s manual-validation sentence is not independently reviewable.