WMS source, decoder and optional transport/resource overrides.
A provider whose acquire respects abort and bounds pixel allocations.
Acquisition rejects with MatchingError: INPUT for invalid
selection, BUDGET before requests exceeding configured or hard limits (32,768
pixels per side, 4096 tiles), SOURCE for transport/decoding failures. Failed
requests are not silently converted to missing-data or geometric partial matches.
Acquire a frozen reference snapshot through sequential, cancellable WMS tiles.
Dimensions round the selected extent/resolution ratio upwards; the snapshot records the exact mapping of the resulting raster to the selected bounds. Requests never expand the search area. Configuration is copied at creation; recreate the provider when source parameters/styles/content revisions change. Hosts handle CORS, authentication and source readiness in their request closure.