chore: add proper documentation (#763)

* chore: generate API ref using `typedoc`

* chore: declutter readme and add links to ytjs.dev

* chore: clean up

docs/api/namespaces/Endpoints/namespaces/GetNotificationMenuEndpoint/README.md

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+[youtubei.js](../../../../README.md) / [Endpoints](../../README.md) / GetNotificationMenuEndpoint
+
+# GetNotificationMenuEndpoint
+
+## Index
+
+### Variables
+
+- [PATH](variables/PATH.md)
+
+### Functions
+
+- [build](functions/build.md)

docs/api/namespaces/Endpoints/namespaces/GetNotificationMenuEndpoint/functions/build.md

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+[youtubei.js](../../../../../README.md) / [Endpoints](../../../README.md) / [GetNotificationMenuEndpoint](../README.md) / build
+
+# Function: build()
+
+> **build**(`opts`): [`IGetNotificationMenuRequest`](../../../../Types/type-aliases/IGetNotificationMenuRequest.md)
+
+Builds a `/get_notification_menu` request payload.
+
+## Parameters
+
+• **opts**: [`GetNotificationMenuEndpointOptions`](../../../../Types/type-aliases/GetNotificationMenuEndpointOptions.md)
+
+The options to use.
+
+## Returns
+
+[`IGetNotificationMenuRequest`](../../../../Types/type-aliases/IGetNotificationMenuRequest.md)
+
+The payload.
+
+## Defined in
+
+[src/core/endpoints/GetNotificationMenuEndpoint.ts:10](https://github.com/LuanRT/YouTube.js/blob/eb21af33db708f0355f4fb15881f5d4fabc7b06c/src/core/endpoints/GetNotificationMenuEndpoint.ts#L10)

docs/api/namespaces/Endpoints/namespaces/GetNotificationMenuEndpoint/variables/PATH.md

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+[youtubei.js](../../../../../README.md) / [Endpoints](../../../README.md) / [GetNotificationMenuEndpoint](../README.md) / PATH
+
+# Variable: PATH
+
+> `const` **PATH**: `"/notification/get_notification_menu"` = `'/notification/get_notification_menu'`
+
+## Defined in
+
+[src/core/endpoints/GetNotificationMenuEndpoint.ts:3](https://github.com/LuanRT/YouTube.js/blob/eb21af33db708f0355f4fb15881f5d4fabc7b06c/src/core/endpoints/GetNotificationMenuEndpoint.ts#L3)