Package ACP builder skills for Codex and Claude

[celesteanglm]

Summary

• add shared ACP builder setup and combined paid checkout skill
• keep each contributed skill self-contained under skills/<skill-name>/, including the Substack checkout example under skills/acp-paid-subscription-checkout/examples/substack
• fold the old checkout handoff behavior into acp-paid-subscription-checkout as handoff and evidence-review modes
• remove hidden project skill aliases; install source skills explicitly with scripts/install-local-skills.sh
• group shared Codex/Claude routing helpers under utilities/model-routing/
• add Claude Desktop ZIP packages for setup and the combined checkout skill
• document supported Codex/Claude CLI and desktop surfaces, GitHub skill references, and Virtuals routing utilities
• add local Codex Responses proxy and Claude Code Router config examples for Virtuals models

Compatibility tested

Surface	Result	Evidence
Codex CLI	Pass	Source skills install into ~/.agents/skills via the installer helper; earlier codex exec --sandbox read-only --ephemeral explicitly invoked $acp-builder-setup and $acp-paid-subscription-checkout successfully.
Codex Desktop app	Pass for local-thread compatibility	Codex official docs say skills are available in CLI, IDE extension, and Codex app, and the setup now uses the same explicit user skill install path instead of repo-hidden aliases.
Claude Code CLI	Pass	Source skills install into ~/.claude/skills via the installer helper; earlier claude -p explicitly invoked /acp-builder-setup and /acp-paid-subscription-checkout successfully.
Claude Desktop app	Package validation pass; UI upload still manual	Both packages/claude-desktop/*.zip pass unzip -t. The checkout ZIP contains the combined skill with handoff/evidence-review mode and must not run live payment actions unless local tools are available.

Validation commands

• scripts/install-local-skills.sh --mode symlink --target both --home <tmp>
• scripts/install-local-skills.sh --mode copy --target both --home <tmp>
• node --check utilities/model-routing/codex-virtuals-proxy/server.mjs
• node -e 'JSON.parse(fs.readFileSync("utilities/model-routing/claude-virtuals-router/config.example.json", "utf8"))'
• scripts/package-claude-desktop-skills.sh
• unzip -t packages/claude-desktop/*.zip
• git diff --check
• earlier: codex exec --sandbox read-only --ephemeral ...
• earlier: claude -p ... --output-format json --max-turns 1

Notes

• Live checkout execution still assumes local acp-cli, browser automation, card issuance, 3DS retrieval, and paid checkout controls.
• Claude Desktop should use the combined checkout skill for handoff prompts or redacted evidence review unless a dedicated local-tool bridge is available.