contentEntry

Wrap one contentKey inside this ContentManager as a ContentEntry. Mirrors findEntry(key) for read-only inspection plus clearEntry / deleteEntry for lifecycle, behind one uniform surface.

One-stop accessor for "this image layer's content view." Lookup order:

1. The layer itself, when it implements ContentEntry directly (e.g. a third-party package layer that is its own cache, like Kropyva-style .kme packages).

2. The layer's tile factory, when it implements ContentEntry (MBTiles, RMaps, ATAK).

3. A ContentManager-backed adapter built from contentManager + the layer's cachedSourceInfo contentKey (GPKG / IDB-cached layers).

Returns null when none of the above apply (network-only layer with no cache wired and no contentManager supplied).

Elevation-coverage counterpart of TiledImageLayer.contentEntry — coverages have no "self-contained file factory" case in the current factory set, so this is just the ContentManager adapter behind a uniform call site.