Revert "feat(mcp): respond with snapshot diff when beneficial (#37500)"

[dgozman]

This reverts commit c92b9a1.

[github-actions]

Test results for "tests 1"

2 failed
❌ [playwright-test] › runner.spec.ts:118 › should ignore subprocess creation error because of SIGINT @macos-latest-node18-1
❌ [playwright-test] › reporter-html.spec.ts:2999 › merged › execSync doesnt produce a second stdout attachment @macos-latest-node18-2

2 flaky

⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:1079 › cli codegen › should not throw csp directive violation errors `@firefox-ubuntu-22.04-node18`
⚠️ [firefox-page] › page/page-emulate-media.spec.ts:144 › should keep reduced motion and color emulation after reload `@firefox-ubuntu-22.04-node18`

46922 passed, 821 skipped

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Merge workflow run.