Harden register pagination and Mol source selection

docs/DATA_SOURCES.md

@@ -335,6 +335,11 @@ reads the official Digitaal Vlaanderen OGC API Features collections
 GeoIntel therefore creates a dated snapshot rather than claiming an annual
 historical series. Raw response pages, request URLs and SHA256 checksums are
 retained as operator evidence.
+The operator follows advertised `next` links and, when a full page omits that
+link, continues with an explicit `startIndex`. This is required because the
+production address collection currently stops advertising `next` at a
+service-side result window even though later offsets remain available. A short
+final page is required before the snapshot is considered complete.
 
 Building polygons are clipped against the exact persisted Area in
 EPSG:31370, transformed to EPSG:4326 and persisted through the normal Dataset