Add JSON byte budgeting to outline

[Widthdom]

Summary

• Add outline --max-json-bytes using the shared whole-row bounded JSON envelope.
• Preserve outline hierarchy and ordering across response:v2 cursor pages, with authoritative totals and complete UTF-8 JSON rows.
• Preserve uncapped output and native option validation, and document the feature in the bilingual guides.

Root cause

outline had its own pagination and output shape but was not registered for the shared bounded-response path. Supporting it also required outline-specific row extraction and validation handling so byte capping could not silently change existing option semantics.

Validation

• dotnet build --no-restore (0 warnings, 0 errors)
• Focused Issue Add a byte budget to outline JSON #4880 tests on net8.0 and net9.0 (4/4 each)
• Broad Outline|JsonEnvelopeWrapper|CliFlagSchema tests on net8.0 and net9.0 (160/160; 158 passed, 2 skipped)
• Help and Issue Add a byte budget to outline JSON #4880 tests (281/281)
• make lint
• Changelog fragment validation (51 fragments)
• git diff --check
• Codex adversarial review; all actionable findings were addressed and covered by tests

The combined full-suite run reported 4 failures on net8.0 and 3 on net9.0. The Issue #4872 and Issue #4602 cases passed when rerun. The remaining watcher instability is already tracked by #4955 and #4966.

Documentation and changelog

• Updated the English and Japanese sections of README.md, USER_GUIDE.md, DEVELOPER_GUIDE.md, and TESTING_GUIDE.md.
• Added changelog.d/unreleased/4880.added.md.

Fixes #4880