Refresh demo tapes: retire editmode, update commands, improve quickstart

- Remove editmode.tape; quickstart now takes the editmode.png screenshot
  and demonstrates adding a new job in edit mode (new:n=diskcheck_home)
- healthcheck_home uses 'uptime', monitor_home uses 'ping -c 1 localhost'
- all-features one-time reminder gains -i (desktop notification example)
- 19 tape commands total (was 24)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

badges/tests.json

@@ -1,6 +1,6 @@
 {
   "schemaVersion": 1,
   "label": "tests",
-  "message": "136 passed",
+  "message": "131 passed",
   "color": "brightgreen"
 }