why

• Reduces docs nesting (e.g. don't have code snippet inside warning)
• Removes . from sub-headers for consistency
• Removes the language tabs when the snippet is language-agnostic bash

what changed

test plan

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Summary by cubic

Flattens Stagehand v4 docs to reduce nested notes and unify code examples for clearer, more consistent rendering. Fixes chopped code blocks in nested notes and removes language tabs for bash snippets (STG-2804).

• Refactors
  • Un-nested code blocks from notes/warnings to fix nested-note rendering (STG-2804).
  • Removed language tabs where snippets are language-agnostic bash.
  • Standardized subheaders by removing trailing periods; aligned titles (e.g., “User data”, “Observe use cases”).
  • Collapsed duplicate CLI/env examples across languages into a single bash block.
  • Reworked logging docs: clarified destinations, split external platforms into Sentry and DataDog with setup steps, and added examples for passing a production logger via logging.onLog.