Add watchdog for missed launchd runs, fix backup path bug + retention

Watchdog (scripts/utils/watchdog.py, com.lotto.watchdog.plist, daily
21:30) checks whether the latest draw or the trained models are older
than the launchd schedule allows and sends a Telegram alert - this
would have caught the Aug 15 update run that silently never fired
(the Mac was presumably asleep; launchd does not retry missed
StartCalendarInterval jobs), instead of that only surfacing on the
next manual check.

Also fixes a real path bug in LottoAPIUpdater.create_backup(): since
self.data_file already points into data/, joining "data","backups"
wrote backups to data/data/backups/ instead of data/backups/ - 73
backups (6.3MB) had been piling up there undetected for months, with
data/data/ only ever gitignored rather than the root cause fixed.
Merges the misplaced backups into the correct location and adds
retention (keep last 30) so backups no longer grow unbounded; applied
the same retention to Eurojackpot's updater in a matching commit
there, which didn't have the path bug but had the same unbounded
growth (85 backups, 2.4MB).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

scripts/automation/com.lotto.watchdog.plist

@@ -0,0 +1,46 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <key>Label</key>
+    <string>com.lotto.watchdog</string>
+
+    <key>ProgramArguments</key>
+    <array>
+        <string>/Users/sebastianfrohlich/Projekte/Lotto/run_watchdog.sh</string>
+    </array>
+
+    <key>StartCalendarInterval</key>
+    <dict>
+        <key>Hour</key>
+        <integer>21</integer>
+        <key>Minute</key>
+        <integer>30</integer>
+    </dict>
+
+    <key>WorkingDirectory</key>
+    <string>/Users/sebastianfrohlich/Projekte/Lotto</string>
+
+    <key>StandardOutPath</key>
+    <string>/Users/sebastianfrohlich/Projekte/Lotto/logs/watchdog_stdout.log</string>
+    <key>StandardErrorPath</key>
+    <string>/Users/sebastianfrohlich/Projekte/Lotto/logs/watchdog_stderr.log</string>
+
+    <key>RunAtLoad</key>
+    <false/>
+
+    <key>EnvironmentVariables</key>
+    <dict>
+        <key>PATH</key>
+        <string>/opt/homebrew/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin</string>
+        <key>LANG</key>
+        <string>de_DE.UTF-8</string>
+    </dict>
+
+    <key>LaunchOnlyOnce</key>
+    <false/>
+
+    <key>Nice</key>
+    <integer>10</integer>
+</dict>
+</plist>