Add one-click Factory.ai Droid setup to Agent Setup

[Divkix]

Summary

Add a one-click Factory integration to the macOS app's Agent Setup pane so users can apply Composer 2.5 / Composer 2.5 Fast as Factory.ai Droid custom models without hand-editing ~/.factory/settings.json.

Today the app already supports one-click setup for OpenCode, Codex, VS Code, Cline, Kilo Code, and pi via AgentProvisioner. Factory.ai Droid supports OpenAI-compatible custom models through its customModels array in ~/.factory/settings.json, so it fits the same pattern.

Proposed behavior

• New .factory case in AgentIntegrationID, surfaced in AgentProvisioner.visibleIntegrationIDs.
• Install writes two customModels entries (composer-2.5, composer-2.5-fast) pointing at the local OpenAI-compatible base URL, using provider: "generic-chat-completion-api" and apiKey: "cursor-local".
• Backs up settings.json before writing (reusing the existing backup helper), strips stale entries by id prefix custom:cursorapi: to avoid duplicates on re-install, and re-indexes entries.
• Status detection mirrors the other integrations (installed / needs update).

Prior art / attribution

The one-click "apply Factory custom models from a local proxy app" approach is adapted from DroidProxy: https://github.com/anand-92/droidproxy — thanks to DroidProxy for the pattern.

I have an implementation ready and will open a PR that closes this issue.