Update PMTiles docs & bump NDK version (#4278)

Co-authored-by: Bart Louwers <bart@emeel.net>

platform/android/docs/data/PMTiles.md

@@ -1,17 +1,44 @@
 # PMTiles
 
-Starting MapLibre Android 11.7.0, using [PMTiles](https://docs.protomaps.com/pmtiles/) as a data source is supported. You can prefix your vector tile source with `pmtiles://` to load a PMTiles file. The rest of the URL continue with be `https://` to load a remote PMTiles file, `asset://` to load an asset or `file://` to load a local PMTiles file.
+{{ activity_source_note("PMTilesActivity.kt") }}
 
-> Note: PMTiles sources do not currently support offline pack downloads.
+Starting MapLibre Android 11.7.0, [PMTiles](https://docs.protomaps.com/pmtiles/) archives are supported as tile sources. Prefix any tile source URL with `pmtiles://` to read from a PMTiles archive:
 
-Oliver Wipfli has made a style available that combines a [Protomaps]() basemap togehter with Foursquare's POI dataset. It is available in the [wipfli/foursquare-os-places-pmtiles](https://github.com/wipfli/foursquare-os-places-pmtiles) repository on GitHub. The style to use is
+- `pmtiles://https://` — stream tiles from a remote file
+- `pmtiles://file://` — read a file from device storage (use `getExternalFilesDir` or `filesDir` for the path)
 
-```
-https://raw.githubusercontent.com/wipfli/foursquare-os-places-pmtiles/refs/heads/main/style.json
+The `pmtiles://` prefix works with any [tile source type](https://maplibre.org/maplibre-style-spec/sources/) (e.g. `vector`, `raster`, `raster-dem`, etc.), from a style JSON or dynamically.
+
+Unlike MapLibre GL JS, which resolves relative URLs against the style's base URL, MapLibre Native requires the URL inside `pmtiles://` to be fully specified (e.g. `pmtiles://https://example.com/tiles.pmtiles`, not `pmtiles://tiles.pmtiles`).
+
+> Note: PMTiles sources do not support offline pack downloads or caching.
+
+## Loading a style that uses PMTiles sources
+
+Load a style JSON that references `pmtiles://` sources. The example below loads a satellite imagery basemap of the Central Alps and sets the initial camera position:
+
+```kotlin
+--8<-- "MapLibreAndroidTestApp/src/main/java/org/maplibre/android/testapp/activity/sources/PMTilesActivity.kt:loadStyle"
 ```
 
-The neat thing about this style is that it only uses PMTiles vector sources. PMTiles can be hosted with a relatively simple file server (or file hosting service) instead of a more complex specialized tile server.
+## Adding a PMTiles source directly
 
-<figure markdown="span">
-  ![Screenshot of PMTiles based style using Protomaps basemap with Foursquare POIs]({{ s3_url("pmtiles-demo.png") }}){ width="300" }
-</figure>
+Add `vector` sources from PMTiles archives to an already-loaded style. The example overlays two places datasets — [Overture Maps](https://overturemaps.org/) (yellow) and [Foursquare OS Places](https://opensource.foursquare.com/os-places/) (blue) — both using `CircleLayer`. The `setSourceLayer` call names the layer within the archive to render:
+
+```kotlin
+--8<-- "MapLibreAndroidTestApp/src/main/java/org/maplibre/android/testapp/activity/sources/PMTilesActivity.kt:addSource"
+```
+
+The same pattern works for `raster` archives using `RasterSource` and `RasterLayer`.
+
+> Note: `raster-dem` sources added programmatically cannot specify `encoding` via the current Android API. Define `raster-dem` sources with terrarium encoding in the style JSON instead, where the `encoding` field is fully supported.
+
+## Loading a local PMTiles file
+
+For files on device storage, use `file://` with an absolute path. The example below uses `getExternalFilesDir(null)` to locate a file downloaded to the app's external files directory:
+
+```kotlin
+--8<-- "MapLibreAndroidTestApp/src/main/java/org/maplibre/android/testapp/activity/sources/PMTilesActivity.kt:loadFromFile"
+```
+
+> Note: `pmtiles://asset://` (files in `src/main/assets/`) is not currently supported. `AssetManagerFileSource` does not implement byte-range reads, which PMTiles requires to read its header and metadata. Use `file://` from device storage instead. See the [open issue](https://github.com/maplibre/maplibre-native/issues/4360) for status.