docs: update hwid-device-limit, receiving-webhooks, and environment-variables documentation to include new user fields and bandwidth usage notifications

docs/features/hwid-device-limit.md

@@ -108,11 +108,3 @@ user-agent: <user_agent>
 The only required item is `x-hwid`. Other headers are optional and can be used to identify the device more accurately.
 
 If your application has the ability to enable additional features based on where the subscription is coming from, Remnawave can send a provider id in the response headers, which you can use to figure out where the subscription is coming from.
-
-```bash
-providerid: 12345
-```
-
-:::info
-Provider ID will be sent only if `PROVIDER_ID` is set in the .env file.
-:::

docs/features/receiving-webooks.md

@@ -56,6 +56,8 @@ The payload will be a JSON object with the following fields:
 - `user.expires_in_48_hours` - The user's subscription will expire in 48 hours.
 - `user.expires_in_24_hours` - The user's subscription will expire in 24 hours.
 - `user.expired_24_hours_ago` - The user's subscription expired 24 hours ago.
+- `user.first_connected` - The user connected to the node for the first time.
+- `user.bandwidth_usage_threshold_reached` - The user's bandwidth usage threshold was reached.
 
 User payload will contain full User object.
 
@@ -94,6 +96,9 @@ hwidDeviceLimit: number | null
 createdAt: string
 updatedAt: string
 
+firstConnectedAt: string | null
+lastTriggeredThreshold: number
+
 activeUserInbounds: Array<{
     uuid: string
     tag: string