backups: daily backup, Back up now, download, restore.sh

A backup is data/backups/selfphoneng-YYYYMMDD-HHMM.tar.gz (mode 0600):
pg_dump, voicemail, custom sounds, music on hold, recordings if asked,
and a manifest. No generated Asterisk config: it holds plaintext
passwords and comes back from the database. The api makes one a day after
backup.time (once-a-minute check, one try a day) and the dashboard warns
when today's is missing. Settings -> Backups sets the schedule, lists them
for download and has Back up now.

scripts/restore.sh <file> refuses a backup made under another APP_SECRET
(the manifest carries a fingerprint, not the secret), asks for yes, then
replaces the database and the folders the backup has.

Tested on two throwaway servers (docker:dind running the real images):
back up on one, restore on the other. That found the api image crashing
on start since M1: tsc doesn't copy auth/common-passwords.txt into dist.
The Dockerfile copies it now and CI loads the app inside the image.

Task: M11-T3

apps/api/Dockerfile

@@ -25,6 +25,8 @@ COPY --from=build /out/node_modules ./node_modules
 COPY --from=build /src/apps/api/dist ./dist
 COPY --from=build /src/apps/web/dist ./public
 COPY --from=build /src/apps/api/src/db/migrations ./dist/db/migrations
+# tsc only emits .js: files the code reads next to itself come over by hand.
+COPY --from=build /src/apps/api/src/auth/common-passwords.txt ./dist/auth/common-passwords.txt
 ENV NODE_ENV=production
 ENTRYPOINT ["/usr/bin/tini","--"]
 CMD ["node","dist/index.js"]