feat: Add Users and Permissions system

[fvanderflier]

What Changed?

• Added a new Project that will serve as a plugin for managing end-users/roles/permissions.
• Use existing controllers to generate meta data for granular permissions per method via new source generator MethodAndPermissionsGenerator
• Add new tables for managing this, that by using the project.
• Came up with convention to call plugins Systems. So this is the UsersAndPermissionsSystem.
• Added some AI Generated docs for this system at https://github.com/codechem/dappi/blob/3c709ca9be79f11e8fdaa11ce297d65b19c5c704/USERS_AND_PERMISSIONS_SETUP.md
• Added a new endpoint for getting this permissions api/roles-and-permissions

TODOS

• In scope of PR

  • Add authorization attributes dynamically so these are evaluated.
  • Add a way to allow external tokens and user registration
  • Add token enrichment with the permissions for the role.
  • Improve the AI generated documentation (simplify).
  • Add end-user registration via email

• Out of scope of PR

  • Add external Auth providers

Some AI-generated diagrams to help/confuse you:

flowchart TD
    A["1️⃣ Source Generator<br/>Scans Controllers"] --> B["2️⃣ Generates<br/>PermissionsMeta.cs"]
    
    B --> C["3️⃣ AddUsersAndPermissionsSystem<br/>DI Setup"]
    
    C --> D["4️⃣ Define Roles<br/>AppRoleAndPermissionsBuilder"]
    
    D --> E["5️⃣ UseUsersAndPermissionsSystem<br/>Initialize & Migrate"]
    
    E --> F["6️⃣ Ready for<br/>Authorization"]
    
    F --> G["User Request"]
    G -->|Check Permissions| H{Has Access?}
    H -->|Yes| I["✓ Allow"]
    H -->|No| J["✗ Deny"]
    
    style A fill:#e1f5ff
    style B fill:#e1f5ff
    style C fill:#fff9c4
    style D fill:#fff9c4
    style E fill:#fff9c4
    style F fill:#c8e6c9
    style G fill:#f8bbd0
    style I fill:#c8e6c9
    style J fill:#ffccbc

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What Happens at Each Step

Step	Component	Action
1️⃣	Source Generator	Discovers all controller methods (CRUD)
2️⃣	PermissionsMeta.cs	Generated file with all available permissions
3️⃣	AddUsersAndPermissionsSystem	Registers DbContext, DbContextAccessor, PermissionsRepository
4️⃣	AppRoleAndPermissionsBuilder	You define which roles can access which methods
5️⃣	UseUsersAndPermissionsSystem	Runs migrations, syncs permissions & roles to database
6️⃣	Authorization	System ready, checks user permissions on each request

Why?

Closes #308

Type of Change

• ✨ New feature (adds new functionality without breaking existing features)

How Did You Test This?

• add new db context

    public class AppUsersAndPermissionsDbContext(DbContextOptions<AppUsersAndPermissionsDbContext> options) : UsersAndPermissionsDbContext(options)
    {
        public DbSet<AppUser> AppUsers { get; set; }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);

            modelBuilder.Entity<AppUser>()
                .HasOne(u => u.Role)
                .WithMany(r => (IEnumerable<AppUser>)r.Users);
        }

• modify program.cs

...
        builder.Services.AddUsersAndPermissionsSystem<AppUsersAndPermissionsDbContext>(PermissionsMeta.Controllers, builder.Configuration);
        builder.Services.AddDappiSwaggerGen();
        
        var app = builder.Build();

        var permBuilder = new AppRoleAndPermissionsBuilder<AppUser>();
        permBuilder.ForRole(UsersAndPermissionsConstants.DefaultRoles.Authenticated)
            .ForController(nameof(TestController))
            .Allow(nameof(TestController.TestCustomMethod))
            .Allow(nameof(TestController.GetAllTests));
    
    await app.UseUsersAndPermissionsSystem<AppUsersAndPermissionsDbContext, AppUser>(permBuilder);
....
        
        app.Run();

• add test controller

public partial class TestController
{
    [HttpGet("test-custom")]
    public IActionResult TestCustomMethod()
    {
        return Ok("This is a test method.");
    }
}

• run endpoint
  http://localhost:5149/api/UsersAndPermissions?roleName=Authenticated
• get response

{
  "TestController": [
    {
      "PermissionName": "TestCustomMethod",
      "Description": "GET/test-custom",
      "Selected": true
    },
    {
      "PermissionName": "GetTests",
      "Description": "GET/Test",
      "Selected": false
    },
    {
      "PermissionName": "GetTest",
      "Description": "GET/Test/{id}",
      "Selected": false
    },
    {
      "PermissionName": "Create",
      "Description": "POST/Test",
      "Selected": false
    },
    {
      "PermissionName": "Update",
      "Description": "PUT/Test/{id}",
      "Selected": false
    },
    {
      "PermissionName": "Delete",
      "Description": "DELETE/Test/{id}",
      "Selected": false
    },
    {
      "PermissionName": "GetAllTests",
      "Description": "GET/Test/get-all",
      "Selected": true
    },
    {
      "PermissionName": "JsonPatchTest",
      "Description": "PATCH/Test/{id}",
      "Selected": false
    }
  ]
}

Review Checklist

• My code follows the project's style and conventions
• I've reviewed my own code for obvious issues
• I've added comments where the code might be confusing
• I've updated relevant documentation (if needed)
• I've tested my changes and they work as expected

Screenshots / Additional Context