Move Dockerfile, entrypoint.sh, docker-compose.yml to repo root

Komodo's build ran `docker build -f Dockerfile .` from inside docker/,
which set the build context to docker/ — a directory that contains neither
package.json nor a nested docker/entrypoint.sh, so both COPY steps failed.
Moving these three files to the repo root makes `docker build .` from the
repo root work with default Komodo settings (no per-build-tool config).

- Dockerfile: update COPY entrypoint.sh path (drops docker/ prefix)
- docker-compose.yml: build.context = . (drops dockerfile: override)
- README.md: docker compose build (drops -f docker/docker-compose.yml)

README.md

@@ -64,7 +64,7 @@ login/status parsing (fetch mocked).
 1. Build the image once locally or on the host:
 
    ```bash
-   docker compose -f docker/docker-compose.yml build
+   docker compose build
    ```
 
 2. Import the shape of the stack into Komodo using `komodo/stack.toml` (or