feat(glyph): ntfy + Slack notification relay

[stackptr]

Summary

Replaces Pushover with a self-hosted ntfy notification bus that forwards to Slack via a bot, providing a unified messaging layer for all glyph services.

Infrastructure

• ntfy-sh runs on 127.0.0.1:2586 as an internal pub/sub bus; services POST to it without touching Slack directly
• ntfy-slack-relay systemd service subscribes to the notifications topic via ntfy's HTTP JSON stream and forwards each message to #updates via chat.postMessage
• Slack bot token stored as an agenix secret, accessible only to the ntfy-sh user
• set -o pipefail ensures curl failures propagate as non-zero so systemd restarts the relay on connection loss

Transmission integration

• script-torrent-done now POSTs to ntfy instead of Pushover
• Message format: Torrent Name finished downloading. View torrents
• Sets Title: Transmission and Tags: transmissionic headers; the relay maps these to the Slack username and icon_emoji fields respectively
• Removed Pushover age secrets (pushover-app-token, pushover-user-token)

Adding future services

Any service on glyph can send a Slack notification with:

curl -s \
  -H "Title: ServiceName" \
  -H "Tags: emoji_name" \
  -d "message text" \
  http://127.0.0.1:2586/notifications

Test plan

• Deploy to glyph and confirm ntfy-sh and ntfy-slack-relay are both active (running)
• Verify subscribers=1 appears in journalctl -u ntfy-sh.service
• Send a test notification: curl -H "Title: Test" -H "Tags: white_check_mark" -d "hello" http://127.0.0.1:2586/notifications
• Confirm message appears in #updates with correct username and icon
• Complete a torrent download and confirm notification arrives with bold name and View torrents link

🤖 Generated with Claude Code

[stackptr]

• feat(glyph): ntfy + Slack notification relay #442 👈 (View in Graphite)
• main

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