docs: update documentation and add Docker configuration for v0.3.0

- Update README.md with v0.3.0 completion status and improved setup instructions
- Update export/progress.md with completed tasks (53/55, 96% progress)
- Update export/architecture.md with current project structure and implementation status
- Add docker-compose.yml with PostgreSQL service
- Add Dockerfile.backend for production builds
- Add frontend/Dockerfile for multi-stage builds
- Update .gitignore with comprehensive rules for Python, Node.js, and Docker

Project status:
- v0.2.0: Database and Backend API ✅
- v0.3.0: Frontend React implementation ✅
- v0.4.0: Reports and visualization (planned)

Dockerfile.backend

@@ -0,0 +1,29 @@
+# Dockerfile.backend
+# Backend FastAPI production image
+
+FROM python:3.11-slim
+
+WORKDIR /app
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y \
+    gcc \
+    libpq-dev \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install uv
+RUN pip install uv
+
+# Copy dependency files
+COPY pyproject.toml uv.lock ./
+
+# Install dependencies
+RUN uv sync --frozen --no-dev
+
+# Copy application code
+COPY src/ ./src/
+COPY alembic/ ./alembic/
+COPY alembic.ini ./
+
+# Run migrations and start application
+CMD ["sh", "-c", "uv run alembic upgrade head && uv run uvicorn src.main:app --host 0.0.0.0 --port 8000"]