Implement 'oqtane module list' command

[markdav-is]

Summary

Implement the oqtane module list command to show available module templates.

Depends On

• Phase 2: Template Discovery (reuses ITemplateService.ListTemplates)

Tasks

• Add module list subcommand to System.CommandLine tree
• Query ITemplateService for available templates
• Display formatted output:

  Available Module Templates:
    internal   Oqtane 10.0 Internal Module Template
    external   Oqtane 10.0 External Module Template
  

• Handle case where no templates are found
• Optionally accept --solution path to look in a specific directory

Acceptance Criteria

• oqtane module list prints available templates with name and description
• Works from within an Oqtane solution directory
• Clear message if no templates found

References

• oqtane-module-cli-specification.md — List Available Templates