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/cli/worker.go

@@ -15,7 +15,7 @@ var publishExample bool
 
 var workerCmd = &cobra.Command{
 	Use:   "worker",
-	Short: "Run the RabbitMQ consumers (dataset parsing + example)",
+	Short: "Run the RabbitMQ consumers (dataset processing, landscape runs + example)",
 	RunE: func(cmd *cobra.Command, args []string) error {
 		ctx, cancel := signalContext()
 		defer cancel()