refactor(db): switch records layer to Prisma

- Replace hand-written node:sqlite queries with a Prisma client using
  the better-sqlite3 driver adapter
- Version the schema with migrations: baseline table, timestamp
  normalisation, and WAL journal mode
- Store timestamps with an explicit UTC offset so they stop being parsed
  as local time
- Show created/updated times on the edit page, formatted with dayjs
- Move the root redirect into next.config to avoid a prerender error
- Run migrations from the container entrypoint before starting the server

BREAKING CHANGE: DNSMASQ_ADMIN_DB_PATH is replaced by DATABASE_URL, which
must be a Prisma connection URL (file:./data/dnsmasq-admin.db). Existing
database files are migrated in place and need no conversion.

pnpm-workspace.yaml

@@ -1,3 +1,14 @@
 allowBuilds:
+  # Prisma's postinstall downloads the query engine binaries and generates the client.
+  # Without these two entries pnpm refuses to add packages (ERR_PNPM_IGNORED_BUILDS).
+  '@prisma/engines': true
+  prisma: true
+  # SQLite driver: prisma ships its own binaries, but better-sqlite3 resolved to v12 requires postinstall(prebuild-install)
+  # to fetch platform binary.
+  better-sqlite3: true
+  # esbuild/workerd ship their platform binaries as optionalDependencies, so there is no
+  # install script that needs running. Declared explicitly so pnpm stops asking.
+  esbuild: false
+  workerd: false
   sharp: false
   unrs-resolver: false