fix: add missing secrets worker to repository

The secrets worker was being ignored due to broad gitignore pattern.
Added exception to allow workers/secrets/ directory while still ignoring actual secrets.

Files added:
- workers/secrets/Dockerfile
- workers/secrets/requirements.txt
- workers/secrets/worker.py

workers/secrets/Dockerfile

@@ -0,0 +1,61 @@
+# FuzzForge Vertical Worker: Secret Detection
+#
+# Pre-installed tools for secret detection:
+# - Gitleaks v8.18.0
+# - TruffleHog v3.63.2
+# - Temporal worker
+
+FROM python:3.11-slim
+
+# Set working directory
+WORKDIR /app
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y \
+    # Build essentials
+    build-essential \
+    # Development tools
+    git \
+    curl \
+    wget \
+    # Cleanup
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Gitleaks v8.18.0
+RUN wget -q https://github.com/gitleaks/gitleaks/releases/download/v8.18.0/gitleaks_8.18.0_linux_x64.tar.gz && \
+    tar -xzf gitleaks_8.18.0_linux_x64.tar.gz && \
+    mv gitleaks /usr/local/bin/ && \
+    chmod +x /usr/local/bin/gitleaks && \
+    rm gitleaks_8.18.0_linux_x64.tar.gz
+
+# Install TruffleHog v3.63.2
+RUN wget -q https://github.com/trufflesecurity/trufflehog/releases/download/v3.63.2/trufflehog_3.63.2_linux_amd64.tar.gz && \
+    tar -xzf trufflehog_3.63.2_linux_amd64.tar.gz && \
+    mv trufflehog /usr/local/bin/ && \
+    chmod +x /usr/local/bin/trufflehog && \
+    rm trufflehog_3.63.2_linux_amd64.tar.gz
+
+# Verify installations
+RUN gitleaks version && trufflehog --version
+
+# Install Python dependencies for Temporal worker
+COPY requirements.txt /tmp/requirements.txt
+RUN pip3 install --no-cache-dir -r /tmp/requirements.txt && \
+    rm /tmp/requirements.txt
+
+# Create cache directory for downloaded targets
+RUN mkdir -p /cache && chmod 755 /cache
+
+# Copy worker entrypoint
+COPY worker.py /app/worker.py
+
+# Add toolbox and AI module to Python path (mounted at runtime)
+ENV PYTHONPATH="/app:/app/toolbox:/app/ai_src:${PYTHONPATH}"
+ENV PYTHONUNBUFFERED=1
+
+# Healthcheck
+HEALTHCHECK --interval=30s --timeout=10s --start-period=40s --retries=3 \
+    CMD python3 -c "import sys; sys.exit(0)"
+
+# Run worker
+CMD ["python3", "/app/worker.py"]