feat: add Easypanel deployment config

- Dockerfile.app: single container with supervisord (API + Worker + Beat + Scanner)
- supervisord.conf: process manager for 4 services in one container
- EASYPANEL.md: step-by-step deploy guide for Easypanel
- EASYPANEL-README.md: repo structure and deploy flow overview

Dockerfile.app

@@ -0,0 +1,52 @@
+# ── Build stage ──────────────────────────────────────────────────────
+FROM python:3.12-slim AS builder
+
+WORKDIR /build
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    gcc libpq-dev curl \
+    && rm -rf /var/lib/apt/lists/*
+
+# Copy pyproject.toml for both api and scanner
+COPY apps/api/pyproject.toml ./api/pyproject.toml
+COPY apps/scanner/pyproject.toml ./scanner/pyproject.toml
+
+# Install API dependencies
+RUN pip install --no-cache-dir --prefix=/install api/.
+
+# Install Scanner dependencies (Playwright + Chromium)
+RUN pip install --no-cache-dir --prefix=/install scanner/. \
+    && playwright install chromium --with-deps
+
+# ── Runtime stage ────────────────────────────────────────────────────
+FROM python:3.12-slim
+
+WORKDIR /app
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    libpq5 curl tini \
+    && rm -rf /var/lib/apt/lists/* \
+    && apt-get clean
+
+# Copy installed dependencies from builder
+COPY --from=builder /install /usr/local
+
+# Copy application code
+COPY apps/api/src ./src
+COPY apps/scanner/src ./src_scanner
+COPY supervisord.conf /etc/supervisord.conf
+
+# Move scanner source into api structure
+RUN if [ -d src_scanner ]; then \
+        cp -r src_scanner/* src/ 2>/dev/null || true; \
+    fi
+
+# Healthcheck for API
+HEALTHCHECK --interval=30s --timeout=5s --start-period=30s --retries=3 \
+    CMD curl -f http://localhost:8000/health || exit 1
+
+# Use tini as init system for proper signal handling
+ENTRYPOINT ["/usr/bin/tini", "--"]
+
+# supervisord manages multiple processes
+CMD ["supervisord", "-c", "/etc/supervisord.conf"]