infra!: added CI/CD pipeline and made various improvements

brain/Dockerfile

@@ -1,6 +1,7 @@
 # Dockerfile for Agent Media
 # Multi-stage build for smaller image size
-ARG PYTHON_VERSION=3.14.2
+ARG PYTHON_VERSION
+ARG PYTHON_VERSION_SHORT
 ARG RUNNER
 # ===========================================
 # Stage 1: Builder
@@ -39,7 +40,27 @@ RUN --mount=type=cache,target=/root/.cache/pip \
     fi
 
 # ===========================================
-# Stage 2: Runtime
+# Stage 2: Testing
+# ===========================================
+FROM builder as test
+RUN --mount=type=cache,target=/root/.cache/pip \
+    --mount=type=cache,target=/root/.cache/pypoetry \
+    --mount=type=cache,target=/root/.cache/uv \
+    if [ "$RUNNER" = "poetry" ]; then \
+        poetry install --no-root; \
+    elif [ "$RUNNER" = "uv" ]; then \
+        uv pip install --system -e .[dev]; \
+    fi
+
+COPY agent/ ./agent/
+COPY application/ ./application/
+COPY domain/ ./domain/
+COPY infrastructure/ ./infrastructure/
+COPY tests/ ./tests/
+COPY app.py .
+
+# ===========================================
+# Stage 3: Runtime
 # ===========================================
 FROM python:${PYTHON_VERSION}-slim-bookworm as runtime
 
@@ -69,7 +90,7 @@ USER appuser
 WORKDIR /home/appuser/app
 
 # Copy Python packages from builder stage
-COPY --from=builder /usr/local/lib/python3.12/site-packages /usr/local/lib/python3.12/site-packages
+COPY --from=builder /usr/local/lib/${PYTHON_VERSION_SHORT}/site-packages /usr/local/lib/${PYTHON_VERSION_SHORT}/site-packages
 COPY --from=builder /usr/local/bin /usr/local/bin
 
 # Copy application code (already owned by appuser)