AppRC 0.27.0

💥 Breaking changes

• Breaking: apprc-gui now exports ConfigEditor for Gradio instead of
  ConfigView for Toga. Affected: applications embedding the old native view.
  Migration: replace the Toga window with application-owned Gradio Blocks
  and call ConfigEditor(MyRC.manage()).render() inside them.

➕ Added

• Added a reusable Gradio settings editor that can initialize declared files,
  choose storage, show effective sources, and save ordinary or secret values.
• Added suggested directory values and completion to interactive setup prompts;
  setup also asks for missing required editable fields.

💔 Changed

• Grouped the six documentation pages under topical H1 headings, with nested
  tables of contents and spacing between major sections. Removed an outdated
  warning that said managed edits had no cross-process coordination.