feat: Revamp CLI with environment variables support and improved DX

[josead]

Summary

This PR introduces several improvements to the metacall-deploy CLI to enhance developer experience and fix known issues:

• Fix Plans selection is not working. #189: Plan selection now correctly respects the user's --plan flag instead of always defaulting to the first available plan
• Environment variables: New -E/--env and --envFile flags for flexible env var configuration
• File filtering: New -I/--ignore flag to exclude files from deployment using glob patterns
• Output modes: New --quiet, --verbose, and --json flags for different output needs
• Dry-run mode: New --dryRun flag to preview deployments without executing them
• Improved help: Reorganized documentation with examples

New CLI Flags

Flag	Description
-E, --env KEY=VALUE	Set environment variable (repeatable)
--envFile <path>	Load env vars from file (repeatable)
-I, --ignore <pattern>	Ignore files matching pattern (repeatable)
-q, --quiet	Suppress non-essential output
-V, --verbose	Show detailed debug output
--json	Output in JSON format for scripting
--dryRun	Preview deployment without deploying

Test plan

• Unit tests pass (npm run unit)
• Build compiles successfully (npm run build)
• Help output displays correctly (metacall-deploy -h)
• Version flag works with JSON output (metacall-deploy --version --json)
• Manual testing of deployment with new env flags
• Manual testing of ignore patterns
• Manual testing of dry-run mode

Examples

# Deploy with environment variables
metacall-deploy -E DB_HOST=localhost -E DB_PORT=5432

# Deploy with env file
metacall-deploy --envFile .env.production

# Preview deployment
metacall-deploy --dryRun

# Deploy ignoring test files
metacall-deploy -I "*.test.js" -I "*.spec.ts"

# Get JSON output for CI/CD
metacall-deploy --json -i