use cliche data in docs

Imported from github/awesome-copilot (MIT, commit 613efc8). This instruction was written by its upstream contributors and has not been reviewed by AI Development Hub. See the bundled LICENSE.

Ensure documentation and examples use only generic, cliche placeholder data — never real or sensitive data sourced from local scripts, configuration, task files, or prompt context.

Scope: **/*.{md,js,mjs,cjs,ts,tsx,jsx,py,json}