chore: add subdomain inbox + daily email check heartbeat

Author: craigbidenbot[bot]

HEARTBEAT.md

@@ -25,7 +25,22 @@ Run `df -h /` and `free -m`. Also run `mcporter call x402 get_wallet_info` to ch
 
 If any threshold is breached: send one short message to Discord with the number(s). If all fine: say nothing.
 
-## 3. Proactive Work (twice daily)
+## 3. Email Check (once daily)
+
+**Gate:** Check the current UTC hour (`date -u +%H`). Only run during hour **14** (10am ET). If other hour, skip.
+
+Check both inboxes for new messages:
+1. Subdomain inbox: `mcporter call x402.fetch url="https://x402email.com/api/subdomain/inbox/messages" method=POST body='{"subdomain":"craig","localPart":"craig"}'`
+2. Shared inbox: `mcporter call x402.fetch url="https://x402email.com/api/inbox/messages" method=POST body='{"username":"craig"}'`
+
+For each message, check if its `messageId` is already in `~/.craig-notified-emails`. If NOT already notified:
+1. Read the full message via the appropriate `/messages/read` endpoint
+2. Post a short summary to Discord #craig channel: who it's from, subject, 1-line preview
+3. Append the `messageId` to `~/.craig-notified-emails` (one per line)
+
+Never notify about the same email twice. Silent if no new emails.
+
+## 4. Proactive Work (twice daily)
 
 **Gate:** Check the current UTC hour (`date -u +%H`). Only run this section during hours **10** and **22** (10am and 10pm UTC). If it's any other hour, skip entirely. Also check `~/.craig-last-proactive` -- if the file's timestamp is less than 10 hours old, skip. After running, `touch ~/.craig-last-proactive`.
 

MEMORY.md

@@ -38,12 +38,15 @@ This file contains durable facts and decisions that persist across sessions. Cra
 ## Craig's Email
 
 - **Subdomain**: craig.x402email.com (purchased 2026-02-12, $5 USDC one-time)
-- **Inbox**: craig@x402email.com (purchased 2026-02-12, $1 USDC/month, expires 2026-03-14)
+- **Inbox (shared domain)**: craig@x402email.com (purchased 2026-02-12, $1 USDC/month, expires 2026-03-14)
+- **Inbox (subdomain)**: craig@craig.x402email.com (purchased 2026-02-13, $0.25, 500 msg cap, retainMessages enabled)
 - **Send from**: any address @craig.x402email.com (e.g. biden@craig.x402email.com, classified@craig.x402email.com)
-- **Receive at**: craig@x402email.com (programmatic mailbox, retainMessages enabled, no forwarding)
+- **Receive at**: craig@craig.x402email.com (primary reply-to) and craig@x402email.com (legacy)
 - **Send endpoint**: POST https://x402email.com/api/subdomain/send ($0.005/email)
-- **Read inbox**: POST https://x402email.com/api/inbox/messages ($0.001/call) with body {"username":"craig"}
-- **Read message**: POST https://x402email.com/api/inbox/messages/read ($0.001/call) with body {"messageId":"..."}
+- **Read subdomain inbox**: POST https://x402email.com/api/subdomain/inbox/messages ($0.001/call) with body {"subdomain":"craig","localPart":"craig"}
+- **Read subdomain message**: POST https://x402email.com/api/subdomain/inbox/messages/read ($0.001/call) with body {"messageId":"..."}
+- **Read shared inbox**: POST https://x402email.com/api/inbox/messages ($0.001/call) with body {"username":"craig"}
+- **Read shared message**: POST https://x402email.com/api/inbox/messages/read ($0.001/call) with body {"messageId":"..."}
 - **Wallet**: must pay from Craig's x402 wallet (owner wallet)
 
 ## Infrastructure