refactor: rename skills and prompts with copilot- prefix for clarity

- Skills: compatibility-checker → copilot-compatibility-checker
- Skills: copilot-audit → copilot-setup-audit
- Skills: customization-selector → copilot-customization-selector
- Skills: skill-builder → copilot-skill-builder
- Prompts: all renamed with copilot- prefix for consistency
- Updated all references in README.md and SKILL.md files
- Makes customizations clearer when imported into other repos

Author: trsdn

…ub/prompts/audit-copilot-setup.prompt.md …ub/prompts/copilot-audit-setup.prompt.md.github/prompts/audit-copilot-setup.prompt.md renamed to .github/prompts/copilot-audit-setup.prompt.md .github/prompts/audit-copilot-setup.prompt.md renamed to .github/prompts/copilot-audit-setup.prompt.md

@@ -1,5 +1,5 @@
 ---
-name: compatibility-checker
+name: copilot-compatibility-checker
 description: Check VS Code and GitHub Copilot feature compatibility. Use this skill when diagnosing why a feature isn't working, checking required settings, or verifying version requirements for experimental features.
 ---
 

…ub/prompts/check-compatibility.prompt.md …ts/copilot-check-compatibility.prompt.md.github/prompts/check-compatibility.prompt.md renamed to .github/prompts/copilot-check-compatibility.prompt.md .github/prompts/check-compatibility.prompt.md renamed to .github/prompts/copilot-check-compatibility.prompt.md

@@ -1,5 +1,5 @@
 ---
-name: customization-selector
+name: copilot-customization-selector
 description: Help decide which GitHub Copilot customization to use (instructions, prompts, agents, or skills). Use this skill when users ask which customization type to create, want to understand the differences, or need guidance choosing between .instructions.md, .prompt.md, .agent.md, or SKILL.md files.
 ---
 

…ithub/prompts/new-custom-agent.prompt.md …thub/prompts/copilot-new-agent.prompt.md.github/prompts/new-custom-agent.prompt.md renamed to .github/prompts/copilot-new-agent.prompt.md .github/prompts/new-custom-agent.prompt.md renamed to .github/prompts/copilot-new-agent.prompt.md

@@ -1,5 +1,5 @@
 ---
-name: copilot-audit
+name: copilot-setup-audit
 description: Audit repository Copilot customization setup. Use this skill to analyze existing configuration, identify missing files, check for best practices, and suggest improvements for agents, prompts, instructions, and skills.
 ---
 

…/prompts/new-instructions-file.prompt.md …ompts/copilot-new-instructions.prompt.md.github/prompts/new-instructions-file.prompt.md renamed to .github/prompts/copilot-new-instructions.prompt.md .github/prompts/new-instructions-file.prompt.md renamed to .github/prompts/copilot-new-instructions.prompt.md

@@ -1,5 +1,5 @@
 ---
-name: skill-builder
+name: copilot-skill-builder
 description: Create and maintain Agent Skills for VS Code and GitHub Copilot. Use this skill when setting up new skills, skill directories, or SKILL.md files. Helps scaffold project skills in .github/skills/ or personal skills in ~/.copilot/skills/.
 ---