fix: Resolve mc config permission error and add MinIO setup documentation

- Replace read-only host mount with dedicated Docker volume for mc config
- Add init-mc-config.sh to initialize mc configuration with proper permissions
- Create setup-mc-alias.sh script to configure MinIO connection
- Add comprehensive MINIO_SETUP.md documentation
- Update docker-compose.dev.yml to use mc-config volume
- Update Dockerfile to run mc config initialization
- Document bcrypt architecture workaround in FIX_ENV_TRUNCATION.md

The mc client can now write to its configuration directory, resolving
the "permission denied" error when connecting to MinIO servers.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

backend/init-mc-config.sh

@@ -0,0 +1,29 @@
+#!/bin/sh
+# Initialize mc config if needed
+
+MC_CONFIG_DIR="/home/node/.mc"
+MC_CONFIG_FILE="$MC_CONFIG_DIR/config.json"
+
+# Create directory if it doesn't exist
+if [ ! -d "$MC_CONFIG_DIR" ]; then
+    echo "Creating mc config directory..."
+    mkdir -p "$MC_CONFIG_DIR"
+fi
+
+# If config doesn't exist, create a basic one
+if [ ! -f "$MC_CONFIG_FILE" ]; then
+    echo "Creating initial mc config..."
+    cat > "$MC_CONFIG_FILE" << 'EOF'
+{
+    "version": "10",
+    "aliases": {}
+}
+EOF
+fi
+
+# Ensure proper ownership
+chown -R node:node "$MC_CONFIG_DIR"
+chmod 755 "$MC_CONFIG_DIR"
+chmod 644 "$MC_CONFIG_FILE"
+
+echo "MC config initialized successfully"