wire gap_filler into schedule engine, API, MCP

crates/application/src/channels/commands.rs

@@ -1,5 +1,5 @@
 use domain::models::ScheduleConfig;
-use domain::value_objects::{ChannelId, RotationPolicy, UserId};
+use domain::value_objects::{ChannelId, MediaFilter, RotationPolicy, UserId};
 
 pub struct CreateChannelCommand {
     pub owner_id: UserId,
@@ -16,6 +16,7 @@ pub struct UpdateChannelCommand {
     pub schedule_config: Option<ScheduleConfig>,
     pub rotation_policy: Option<RotationPolicy>,
     pub auto_schedule: Option<bool>,
+    pub gap_filler: Option<Option<MediaFilter>>,
 }
 
 pub struct DeleteChannelCommand {

crates/application/src/channels/tests/update.rs

@@ -45,6 +45,7 @@ async fn updates_channel_name() {
             schedule_config: None,
             rotation_policy: None,
             auto_schedule: None,
+            gap_filler: None,
         },
     )
     .await
@@ -82,6 +83,7 @@ async fn update_fails_if_not_owner() {
             schedule_config: None,
             rotation_policy: None,
             auto_schedule: None,
+            gap_filler: None,
         },
     )
     .await;
@@ -108,6 +110,7 @@ async fn update_nonexistent_channel_returns_not_found() {
             schedule_config: None,
             rotation_policy: None,
             auto_schedule: None,
+            gap_filler: None,
         },
     )
     .await;
@@ -148,6 +151,7 @@ async fn update_config_creates_snapshot() {
             schedule_config: Some(new_config),
             rotation_policy: None,
             auto_schedule: None,
+            gap_filler: None,
         },
     )
     .await
@@ -187,6 +191,7 @@ async fn update_without_config_skips_snapshot() {
             schedule_config: None,
             rotation_policy: None,
             auto_schedule: None,
+            gap_filler: None,
         },
     )
     .await
@@ -225,6 +230,7 @@ async fn update_description_clear() {
             schedule_config: None,
             rotation_policy: None,
             auto_schedule: None,
+            gap_filler: None,
         },
     )
     .await
@@ -243,6 +249,7 @@ async fn update_description_clear() {
             schedule_config: None,
             rotation_policy: None,
             auto_schedule: None,
+            gap_filler: None,
         },
     )
     .await

crates/application/src/channels/update.rs

@@ -35,6 +35,9 @@ pub async fn execute(deps: &ChannelCommandDeps, cmd: UpdateChannelCommand) -> Do
     if let Some(auto) = cmd.auto_schedule {
         channel.set_auto_schedule(auto);
     }
+    if let Some(gap_filler) = cmd.gap_filler {
+        channel.set_gap_filler(gap_filler);
+    }
 
     deps.channel_command.save(&channel).await?;