[matthewp]

Changes

• Brings back the Discord assistant from Discord assistant: ask Factory about the codebase, then file issues or open PRs from a thread #54 (reverted in Revert the Discord assistant until Message Content is approved #56) and runs it on Houston's bot, which already has the Message Content intent, so the assistant reads the whole thread. Factory's existing advisory triage also moves to Houston once its token is swapped in, keeping everything on one bot.
• Houston's interactions endpoint already serves its own slash commands and buttons, so the assistant uses no buttons and no interactions endpoint. A maintainer confirms a draft issue or PR plan by mentioning the bot ("@houston file it", "@houston open the PR"). The agent calls a new confirm_proposal tool. Trusted workflow code then checks the proposal belongs to the thread and is still pending, and claims it once in the thread coordinator. Only after that does it file the issue or queue the PR job.
• Only Core and Maintainer can trigger it (role check on every mention), and only the mention itself can confirm, never other text in the thread.
• Houston has no persistent Gateway connection, and its weekly stats job only connects briefly, so Factory's Gateway connection doesn't conflict with it. Factory never handles Houston's interactions.
• Sets the server and role ids in wrangler.jsonc, and adds a v9 migration recreating the Durable Object classes that v8 deleted.

Testing

• tests/discord-assistant.test.ts: replaces the button tests with proposal/confirmation parsing and the new proposal message and status formatting; the skill test now checks for confirm_proposal.
• Drops tests/discord-interactions.test.ts along with the interactions endpoint.
• Restores the Gateway, thread coordinator, and config tests from Discord assistant: ask Factory about the codebase, then file issues or open PRs from a thread #54 unchanged.

Docs

• README documents confirmation by mention and the bot requirements (Message Content, permissions); the interactions endpoint setup is gone.