Add Slack connector

[mikeastock]

Summary

• Adds Slack as a first-class chat service with config types, discovery, /chat-config guided setup, and JSON app manifest generation.
• Implements a Socket Mode live adapter using @slack/socket-mode plus Web API send/edit/delete/file upload/catch-up support via @slack/web-api.
• Adds Slack markdown normalization, routing, docs, command labels, required Slack dependencies, and Slack thread parent tracking for runtime replies.
• Adds an access-policy allowedBotIds allowlist so trusted Slack bot/app messages can bypass the default bot/self-message filter without disabling bot filtering globally; /chat-config supports both discovered bot entries and manual Slack bot_id entry.

Review & Testing Checklist for Human

• Run /chat-config → Create account → Slack with a real Slack app and verify the generated JSON manifest imports cleanly.
• Configure a Slack channel access policy with Allowed bots containing the test app bot_id, then verify an API-authored test bot message can trigger a threaded reply.
• Connect a configured Slack channel/DM and verify mention-trigger behavior in channels and message-trigger behavior in DMs.
• Send/receive at least one attachment in Slack to verify files:read/files:write handling.

Notes

• Local static checks pass: npm run check.
• Live Slack validation passed with provided repo-scoped secrets: auth.test, team.info, conversation discovery, users.list, Socket Mode connect/disconnect, inbound event receipt in #kitbot-test, and outbound diagnostic replies posted back to Slack threads.
• Official allowlisted bot retest passed with allowedBotIds: ["B0B3PR8SQN4"]: Slack API-authored message 1778444873.257499 had bot_id: B0B3PR8SQN4, queued one mention job despite ignoreBots: true, and pi-chat replied in the same thread with marker official-allowed-bot-reply-1778444871831.

Link to Devin session: https://app.devin.ai/sessions/eedfb7186c524650a0fe27f319cb292f
Requested by: @mikeastock

[devin-ai-integration]

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[devin-ai-integration]

Slack connector runtime test results

Tested locally against Slack workspace stogo using real Slack API/Socket Mode credentials. No screen recording: this was shell/API-only.

Escalations / constraints first:

• Newly generated real-time user-authored inbound via API is untested: SLACK_PI_CHAT_USER_TOKEN chat.postMessage was stored by Slack with bot_id/app_id, so it is app/bot-originated and filtered by pi-chat's bot/self guard.
• Incoming webhook was not used for inbound proof because webhook posts are also app/bot-originated.
• I verified adapter/runtime/threading using an existing real human-authored Slack mention from #kitbot-test history.

Assertions:

• passed — Slack discovery found workspace T02RMJSAC (stogo), bot kittest, and channel C0AC4U15CN4 (#kitbot-test).
• passed — Socket Mode connected and caught up a historical human-authored message with no adapter errors.
• passed — Selected inbound had sourceHadBotId: false, mentionedBot: true, and queued exactly one job.
• passed — Runtime stored replyToMessageId as 1778439064.934739 for both inbound and outbound records.
• passed — Slack reply 1778440723.395009 was posted to thread 1778439064.934739 and contained marker reply-ok-history-1778440720091.
• untested — Newly generated real-time user-authored inbound via API; Slack stored the API post with bot_id/app_id.
• passed — npm run check completed successfully.

Slack E2E assertions	JSONL runtime log

API-generated inbound constraint	Static check

Devin session: https://app.devin.ai/sessions/eedfb7186c524650a0fe27f319cb292f

[devin-ai-integration]

Allowed Slack bot E2E retest results

Tested locally against Slack workspace stogo using real Slack API/Socket Mode credentials. No screen recording: this was shell/API-only.

Escalations / constraints first:

• No CI checks are configured for this PR (0 passed, 0 failed, 0 pending).
• Slack user discovery did not expose the API test app bot ID, so I added and tested the manual bot_id entry path in /chat-config before rerunning this test.

Assertions:

• passed — Workspace/channel validation matched T02RMJSAC and C0AC4U15CN4.
• passed — Manual allowlist config represented exactly allowedBotIds: ["B0B3PR8SQN4"] with ignoreBots: true.
• passed — Source Slack message 1778444873.257499 had bot_id: B0B3PR8SQN4, app_id: A0B2Z5CMK52, and marker official-allowed-bot-1778444871831.
• passed — Slack adapter accepted the bot-authored message and preserved botId: B0B3PR8SQN4, isBot: true, mentionedBot: true, and replyToMessageId: 1778444873.257499.
• passed — Runtime queued one mention job despite ignoreBots: true because the bot ID was allowlisted.
• passed — Slack reply 1778444874.103149 landed in thread 1778444873.257499 with marker official-allowed-bot-reply-1778444871831.
• passed — JSONL log contains inbound → checkpoint → job_queued → outbound → job_completed with outbound replyToMessageId: 1778444873.257499.
• passed — npm run check completed successfully.

Devin session: https://app.devin.ai/sessions/eedfb7186c524650a0fe27f319cb292f