feat: add module workflow tools (validate, inspect, package)

Add three new commands for Redis Enterprise 8.x module development:

module validate - Validate module.json against RE8 schema
- Checks required fields (module_name)
- Warns about recommended fields (version, semantic_version, min_redis_version)
- Highlights missing compatible_redis_version (important for RE8 upgrade tests)
- Strict mode (--strict) requires all recommended fields
- JSON output format supported

module inspect - Inspect packaged module zip files
- Shows package contents with file sizes
- Parses and displays module.json metadata
- Validates RE8-compatible structure (flat zip, module.json + .so at root)
- Full mode (--full) shows all command definitions
- Detects common packaging errors (subdirectories, missing files)

module package - Create RE8-compatible module zip
- Packages module binary + module.json into flat zip structure
- Optional validation before packaging (--validate)
- Creates proper structure for user_defined_modules bootstrap

These tools support the RE8 native module packaging format which replaced
the older RAMP-based packaging. The new format is a simple zip with
module.json and the .so file at the root level.

Examples:
  redisctl enterprise module validate ./module.json
  redisctl enterprise module validate ./module.json --strict
  redisctl enterprise module inspect ./package.zip
  redisctl enterprise module inspect ./package.zip --full
  redisctl enterprise module package --module ./mod.so --metadata ./module.json --out ./pkg.zip

Author: joshrotenberg