Registry API Refactoring (#144)

* Refactor core to use a flexible registry pattern

- Introduce a new registry mechanism for mailer providers
- Extract mailer provider enum to a separate file
- Implement dynamic mailer loading using a registry
- Update package dependencies and exports
- Improve modularity and extensibility of mailer implementation

* Refactor monitoring and billing services to use a flexible registry pattern

- Introduce a shared registry mechanism for dynamic service loading
- Replace static switch-based implementations with a registry-based approach
- Update instrumentation, CMS, and monitoring services to use the new registry
- Improve modularity and extensibility of service implementations
- Add Zod-based type-safe provider validation

* Simplify async registration in monitoring and billing services

- Remove unnecessary async wrappers for no-op registrations
- Update type definitions to support both async and sync registration functions
- Standardize registration approach for Paddle and Sentry providers

* Remove Tailwind package from packages where it is not being needed

* Remove Tailwind config references from pnpm-lock.yaml

* Update instrumentation registry to support dynamic monitoring providers

- Modify type definition to use NonNullable MonitoringProvider
- Import MonitoringProvider type from get-monitoring-provider
- Enhance type safety for instrumentation registration

packages/mailers/core/package.json

@@ -14,10 +14,11 @@
   },
   "devDependencies": {
     "@kit/eslint-config": "workspace:*",
+    "@kit/mailers-shared": "workspace:*",
     "@kit/nodemailer": "workspace:*",
     "@kit/prettier-config": "workspace:*",
     "@kit/resend": "workspace:*",
-    "@kit/tailwind-config": "workspace:*",
+    "@kit/shared": "workspace:*",
     "@kit/tsconfig": "workspace:*",
     "@types/node": "^22.13.0",
     "zod": "^3.24.1"