Rename agent skills SDK target to skills

[ChiragAgg5k]

Summary

• Rename the agent-skills SDK target and language class to skills / Skills.
• Move shared skill templates from templates/agent-skills to templates/skills and update plugin generators to use the new base class/templates.
• Update README/AGENTS docs, CLI skill installer text, and the installer repository URL to https://github.com/appwrite/skills.
• Add SDK target validation so the removed agent-skills target fails instead of silently succeeding.

Testing

• php example.php skills
• php example.php cli
• php example.php cursor-plugin
• php example.php claude-plugin
• php example.php codex-plugin
• composer lint-twig
• composer refactor:check
• vendor/bin/phpunit --testsuite Unit
• git diff --check

[greptile-apps]

Greptile Summary

This PR renames the agent-skills SDK target and its AgentSkills PHP class to skills / Skills, moves all shared templates from templates/agent-skills/ to templates/skills/, updates all three plugin subclasses (ClaudePlugin, CodexPlugin, CursorPlugin) to extend the renamed parent, and updates user-facing strings and documentation throughout.

• All template include() paths, PHP class names, CLI user-facing strings, example.php generation blocks, and the skills repository URL are consistently updated; no stale agent-skills references remain in source code or tests.
• example.php gains an explicit SDK-target allowlist with a throw on unknown targets and an exit(1) in the catch block, so bad targets and generation errors now surface as non-zero exit codes in CI rather than silently succeeding.
• The internal wiki files under .greptile-internal/context/wiki/ still refer to AgentSkills and agent-skills in several places and should be updated to match the rename.

Confidence Score: 4/5

Safe to merge; all source files, tests, templates, and user-facing documentation are consistently updated with no functional logic changes beyond the rename.

The rename is thorough across PHP classes, Twig templates, CLI TypeScript, and markdown docs. The only gap is the internal Greptile wiki context files which still reference the old AgentSkills class name and agent-skills template path in several places — a minor documentation inconsistency that won't break anything at runtime.

.greptile-internal/context/wiki/docs/language-classes.md, .greptile-internal/context/wiki/docs/spec-parsing.md, and .greptile-internal/context/wiki/index.md — all contain stale AgentSkills/agent-skills references.

Important Files Changed

Filename	Overview
src/SDK/Language/Skills.php	Renamed from AgentSkills.php; class, getName(), and all template references updated correctly to skills/.
example.php	Adds SDK target validation list, changes agent-skills to skills throughout, and adds exit(1) in the catch block so failures surface as non-zero exit codes in CI.
src/SDK/Language/ClaudePlugin.php	Extends Skills instead of AgentSkills; all agent-skills/ template references updated to skills/.
src/SDK/Language/CodexPlugin.php	Extends Skills instead of AgentSkills; all agent-skills/ template references updated to skills/.
src/SDK/Language/CursorPlugin.php	Extends Skills instead of AgentSkills; no other changes required as it inherits getSkillFiles() from the parent.
templates/cli/lib/utils.ts	Updates SKILLS_REPO URL from appwrite/agent-skills to appwrite/skills and renames the section comment; no logic changes.
templates/cli/lib/commands/init.ts	Updates three user-facing strings from "agent skills" to "skills"; no logic changes.
templates/cli/lib/parser.ts	Updates init command description string from "agent skills" to "skills"; no logic changes.

_{Reviews (1): Last reviewed commit: "Rename agent skills SDK target to skills" | Re-trigger Greptile}