feat(landscape): HTTP API, worker consumer, wiring, docs

Adds the /landscape routes (slots, slot upload, runs, run detail, results),
mounts them in the router, wires the landscape repository, job publisher,
godal raster IO and Compute into the composition root, and registers the
gis-landscape-runner consumer in the worker.

Also fixes the Dockerfile so the image actually runs: godal's cgo needs g++,
and the runtime base must match the builder's Alpine release or libgdal's
soname does not resolve.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

internal/transport/http/router.go

@@ -16,7 +16,9 @@ type RouterDeps struct {
 	Datasets   *DatasetHandler
 	// DatasetGroups serves the /dataset-groups routes.
 	DatasetGroups *DatasetGroupHandler
-	OpenAPISpec   []byte
+	// Landscape serves the /landscape routes.
+	Landscape   *LandscapeHandler
+	OpenAPISpec []byte
 }
 
 // NewRouter builds the application's HTTP handler with middleware and routes.
@@ -40,6 +42,7 @@ func NewRouter(deps RouterDeps) http.Handler {
 	r.Route("/categories", deps.Categories.Register)
 	r.Route("/datasets", deps.Datasets.Register)
 	r.Route("/dataset-groups", deps.DatasetGroups.Register)
+	r.Route("/landscape", deps.Landscape.Register)
 
 	return r
 }