feat(test runner): add -G alias for grep-invert

[KirtiRamchandani]

Problem

• Closes [Feature]: Implement short-form option for command line argument --grep-invert #41036.
• --grep has the short form -g, but --grep-invert does not have a matching short form.

Root cause

• The test runner CLI only registered the long --grep-invert <grep> option.

Solution

• Register -G as the short option for --grep-invert.
• Update the CLI documentation table.
• Add test runner coverage that exercises -G through the real CLI path.

Tests run

• npm ci
• npm run build
• npm run ttest -- tests/playwright-test/match-grep.spec.ts
• npx eslint packages/playwright/src/program.ts tests/playwright-test/match-grep.spec.ts
• node utils/doclint/cli.js docs/src/test-cli-js.md
• node packages/playwright/cli.js test --help
• git diff --check

[github-actions]

Test results for "MCP"

7230 passed, 1103 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

4 flaky

⚠️ [chromium-library] › library/beforeunload.spec.ts:130 › should support dismissing the dialog multiple times `@ubuntu-22.04-chromium-tip-of-tree`
⚠️ [chromium-library] › library/video.spec.ts:719 › screencast › should work with video+trace `@chromium-ubuntu-22.04-node20`
⚠️ [chromium-library] › library/video.spec.ts:275 › screencast › should capture navigation `@chromium-ubuntu-22.04-node22`
⚠️ [firefox-page] › page/page-emulate-media.spec.ts:144 › should keep reduced motion and color emulation after reload `@firefox-ubuntu-22.04-node20`

44097 passed, 865 skipped

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Merge workflow run.