The NpgsqlDataSource singleton factory in AddJellyfinDbContext calls
sp.GetRequiredService<IServerConfigurationManager>() to read pool settings.
During ApplyStartupMigrationAsync, only a subset of services are registered
in the startup service collection — IServerConfigurationManager was missing,
causing a fatal DI resolution failure when DatabaseType=Jellyfin-PostgreSQL.
Fix: register startupConfigurationManager as IServerConfigurationManager in
the migrationStartupServiceProvider service collection.
Also remove JELLYFIN_CONFIG_DIR=/config from Dockerfile.runtime ENV block.
When configDir == dataDir, MakeSanityCheckOrThrow writes .jellyfin-config at
the datadir root, then immediately throws because it expected .jellyfin-data.
Removing the env var lets configDir default to $JELLYFIN_DATA_DIR/config.
DinD overlay-on-overlay throttles dotnet child container to ~11s CPU/3h wall time.
Solution: dotnet restore+publish run on native runner FS (~10min), then
Dockerfile.runtime just COPYs the pre-built publish-output/ directory.
This brings build time from 3h+ (stuck) to ~10-15 minutes total.
mat