Research and add Antigravity connector support

[chubes4]

Parent: #76

Goal

Determine the correct Antigravity integration surface and add generated connector output only after the official path is known.

Research questions

• Does Antigravity consume VS Code Marketplace extensions directly?
• Does it support Open VSX or a separate extension registry?
• Does it have a documented MCP config path?
• Does it support rules, skills, plugins, or workspace instructions?
• Can the shared wordpress-studio and wordpress-telemetry MCP setup be represented in its native format?

Implementation path

• Document official references before adding generated files.
• Add Antigravity generation to scripts/build-plugins.mjs only for supported native artifacts.
• Add verifier coverage in scripts/verify-plugins.mjs.
• Add docs and manual test steps for installation/configuration.

Acceptance criteria

• Official integration surface is documented with source links.
• Unsupported assumptions are explicitly ruled out.
• Generated output exists only if Antigravity has a documented native path.
• pnpm build and pnpm verify pass after implementation.

AI assistance

• AI assistance: Yes
• Tool(s): OpenCode (GPT-5.5)
• Used for: Drafting issue scope and acceptance criteria from planning discussion.

[chubes4]

Research branch/worktree prepared by coding subagent.

Worktree: /Users/chubes/Developer/build-with-wordpress@antigravity-research
Branch: antigravity-research

Conclusion:

• Added docs-only research note.
• Official Antigravity docs support MCP, skills, rules, workflows, and plugins.
• Official docs did not confirm VS Code Marketplace, Open VSX, VSIX install, arbitrary VS Code extension compatibility, or a third-party plugin distribution/update path.
• No generated Antigravity output was added.

Files changed:

• docs/README.md
• docs/antigravity-connector-research.md

Verification:

• pnpm build && pnpm verify passed after generated outputs were rebuilt.

Next:

• Get product/official confirmation for a minimal local .agents/plugins/wordpress-studio/ plugin path before adding generator support.

[chubes4]

Closed #85 rather than merging Antigravity research docs into the repo. Keep this as issue-tracked research until there is a confirmed implementation path and distribution model.