feat(webhooks): wire event bus into state, routes, and scheduler

k-tv-backend/api/src/dto.rs

@@ -72,6 +72,8 @@ pub struct CreateChannelRequest {
     pub access_mode: Option<domain::AccessMode>,
     /// Plain-text password; hashed before storage.
     pub access_password: Option<String>,
+    pub webhook_url: Option<String>,
+    pub webhook_poll_interval_secs: Option<u32>,
 }
 
 /// All fields are optional — only provided fields are updated.
@@ -91,6 +93,9 @@ pub struct UpdateChannelRequest {
     pub logo: Option<Option<String>>,
     pub logo_position: Option<domain::LogoPosition>,
     pub logo_opacity: Option<f32>,
+    /// `Some(None)` = clear, `Some(Some(url))` = set, `None` = unchanged.
+    pub webhook_url: Option<Option<String>>,
+    pub webhook_poll_interval_secs: Option<u32>,
 }
 
 #[derive(Debug, Serialize)]
@@ -107,6 +112,8 @@ pub struct ChannelResponse {
     pub logo: Option<String>,
     pub logo_position: domain::LogoPosition,
     pub logo_opacity: f32,
+    pub webhook_url: Option<String>,
+    pub webhook_poll_interval_secs: u32,
     pub created_at: DateTime<Utc>,
     pub updated_at: DateTime<Utc>,
 }
@@ -126,6 +133,8 @@ impl From<domain::Channel> for ChannelResponse {
             logo: c.logo,
             logo_position: c.logo_position,
             logo_opacity: c.logo_opacity,
+            webhook_url: c.webhook_url,
+            webhook_poll_interval_secs: c.webhook_poll_interval_secs,
             created_at: c.created_at,
             updated_at: c.updated_at,
         }