Add HTTP API server, Android app, and CI build/publish pipeline

- docker-compose.yml + tooling-container/src/server.py: serve
  preprocess/OCR/extract over an async job API (POST /jobs, GET
  /jobs/{id}) instead of manual host-script runs per receipt
- android/: Kotlin/Compose app - capture a receipt photo, poll job
  progress, review/edit extracted fields, save locally (Room), export
  to CSV/ODS
- .gitea/workflows/build.yml: build the debug APK and publish it to
  dl.ladkau.de on push
- build-image.sh: also pull ollama/ollama so all pipeline images are
  ready after one script
- add project logo (also used for the app's launcher icon/splash)

build-image.sh

@@ -1,7 +1,9 @@
 #!/usr/bin/env bash
 # Builds the fuelish tools image (tooling-container/Dockerfile) locally, tagged with
-# tooling-container/VERSION and :latest. Does not push - test it with the numbered
-# pipeline scripts first, then publish with ./upload-image.sh.
+# tooling-container/VERSION and :latest, and pulls the other image the pipeline
+# needs (ollama/ollama, used by 0_run_ollama.sh) so all images are ready before
+# a pipeline run. Does not push - test it with the numbered pipeline scripts
+# first, then publish with ./upload-image.sh.
 set -euo pipefail
 
 cd "$(dirname "${BASH_SOURCE[0]}")"
@@ -29,6 +31,9 @@ docker build \
     -t "$IMAGE:latest" \
     "$ROOT/tooling-container"
 
+echo "== Pulling ollama/ollama (used by 0_run_ollama.sh) =="
+docker pull ollama/ollama
+
 echo "== Done =="
 echo "Image: $IMAGE:$VERSION (and :latest)"
 echo "Test it with the numbered pipeline scripts, then publish with ./upload-image.sh"