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>

scripts/setup-mc-alias.sh

@@ -0,0 +1,50 @@
+#!/bin/bash
+
+echo "========================================"
+echo "MinIO WebUI - Setup MC Alias"
+echo "========================================"
+echo ""
+
+# Check if .env exists
+if [ ! -f .env ]; then
+    echo "Error: .env file not found"
+    echo "Please create .env file from .env.example"
+    exit 1
+fi
+
+# Source the .env file
+export $(cat .env | grep -v '^#' | xargs)
+
+# Check required variables
+if [ -z "$MINIO_ENDPOINT" ] || [ -z "$MINIO_ACCESS_KEY" ] || [ -z "$MINIO_SECRET_KEY" ] || [ -z "$DEFAULT_MINIO_ALIAS" ]; then
+    echo "Error: Missing required MinIO configuration in .env"
+    echo "Please ensure the following are set:"
+    echo "  - MINIO_ENDPOINT"
+    echo "  - MINIO_ACCESS_KEY" 
+    echo "  - MINIO_SECRET_KEY"
+    echo "  - DEFAULT_MINIO_ALIAS"
+    exit 1
+fi
+
+echo "Setting up MinIO alias: $DEFAULT_MINIO_ALIAS"
+echo "Endpoint: $MINIO_ENDPOINT"
+echo ""
+
+# Set up the alias in the container
+docker exec minio-webui-backend-dev sh -c "mc alias set $DEFAULT_MINIO_ALIAS $MINIO_ENDPOINT $MINIO_ACCESS_KEY $MINIO_SECRET_KEY"
+
+if [ $? -eq 0 ]; then
+    echo ""
+    echo "✅ MinIO alias configured successfully!"
+    echo ""
+    echo "Testing connection..."
+    docker exec minio-webui-backend-dev sh -c "mc ls $DEFAULT_MINIO_ALIAS" 2>&1 | head -5
+else
+    echo ""
+    echo "❌ Failed to configure MinIO alias"
+    echo ""
+    echo "Please check:"
+    echo "1. MinIO endpoint is accessible: $MINIO_ENDPOINT"
+    echo "2. Access credentials are correct"
+    echo "3. Backend container is running"
+fi