Revert "SaaS fixes (#6578)"

This reverts commit ddf78d11ae.

engine/Dockerfile

@@ -10,27 +10,18 @@ RUN apt-get update \
     && rm /tmp/task.deb \
     && rm -rf /var/lib/apt/lists/*
 
-# Source under /app/engine/ to match root Taskfile's `includes.engine.dir: engine`.
-WORKDIR /app/engine
+WORKDIR /app
 
-COPY pyproject.toml uv.lock .env ./
+COPY pyproject.toml uv.lock Taskfile.yml .env ./
+COPY .taskfiles/ ./.taskfiles/
 COPY scripts/ ./scripts/
 RUN --mount=type=cache,target=/root/.cache/uv \
     uv sync --frozen --no-dev
 
 COPY src/ ./src/
 
-WORKDIR /app
-COPY Taskfile.yml ./
-COPY .taskfiles/ ./.taskfiles/
-
-ENV PATH="/app/engine/.venv/bin:$PATH"
+ENV PATH="/app/.venv/bin:$PATH"
 ENV PYTHONUNBUFFERED=1
-ENV STIRLING_ENGINE_WORKERS=4
-# Container runs on a fixed port; skip the host-only free-port probe (its script
-# is not shipped in the image). engine:run honours these.
-ENV ENGINE_PORT_PROBE=false
-ENV STIRLING_ENGINE_PORT=5001
 
 EXPOSE 5001