Initial release of CHORUS Development Images

This commit establishes the foundation for language-specific development
container images used by CHORUS autonomous agents.

Features:
- Multi-stage Dockerfile with 7 layered images
- Base Debian Bookworm image with common tools
- Language-specific images: Rust, Go, Python, Node.js, Java, C/C++
- Standardized /workspace/{input,data,output} structure
- Automated CI/CD pipeline for weekly security updates
- Comprehensive test suite for all images
- Full documentation (README, USAGE, MAINTENANCE)

Images available:
- chorus/base:1.0.0 (~200MB)
- chorus/rust-dev:1.0.0 (~1.2GB)
- chorus/go-dev:1.0.0 (~600MB)
- chorus/python-dev:1.0.0 (~800MB)
- chorus/node-dev:1.0.0 (~700MB)
- chorus/java-dev:1.0.0 (~1.5GB)
- chorus/cpp-dev:1.0.0 (~900MB)

🤖 Generated with Claude Code (https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

tests/test-rust-dev.sh

@@ -0,0 +1,32 @@
+#!/bin/bash
+# Test script for Rust development image
+
+set -e
+
+IMAGE="${REGISTRY:-registry.home.deepblack.cloud/chorus}/rust-dev:latest"
+
+echo "🧪 Testing Rust image: $IMAGE"
+
+# Test Rust toolchain
+echo "  ✓ Checking Rust toolchain..."
+docker run --rm "$IMAGE" rustc --version > /dev/null || exit 1
+docker run --rm "$IMAGE" cargo --version > /dev/null || exit 1
+docker run --rm "$IMAGE" rustfmt --version > /dev/null || exit 1
+docker run --rm "$IMAGE" cargo clippy --version > /dev/null || exit 1
+
+# Test development tools
+echo "  ✓ Checking Rust tools..."
+docker run --rm "$IMAGE" which ripgrep > /dev/null || exit 1
+docker run --rm "$IMAGE" which fd > /dev/null || exit 1
+
+# Test build capability
+echo "  ✓ Testing Rust build..."
+docker run --rm "$IMAGE" bash -c '
+  cd /tmp && \
+  cargo init --name test-project --quiet && \
+  cd test-project && \
+  cargo build --release --quiet && \
+  ./target/release/test-project
+' || exit 1
+
+echo "✅ Rust image tests passed"