wire gap_filler into schedule engine, API, MCP

crates/mcp/src/server.rs

@@ -47,6 +47,7 @@ pub struct UpdateChannelParams {
     pub timezone: Option<String>,
     pub description: Option<String>,
     pub schedule_config_json: Option<String>,
+    pub gap_filler_json: Option<String>,
 }
 
 #[derive(Debug, Deserialize, JsonSchema)]
@@ -98,7 +99,7 @@ impl KTvMcpServer {
         channels::create_channel(&self.channel_cmd_deps, self.owner_id, &p.name, &p.timezone).await
     }
 
-    #[tool(description = "Update channel name, timezone, description, and/or schedule config")]
+    #[tool(description = "Update channel name, timezone, description, schedule config, and/or gap_filler")]
     async fn update_channel(&self, #[tool(aggr)] p: UpdateChannelParams) -> String {
         let id = match parse_uuid(&p.id) {
             Ok(id) => id,
@@ -114,6 +115,17 @@ impl KTvMcpServer {
             },
             None => None,
         };
+        let gap_filler = match p.gap_filler_json {
+            Some(json) if json == "null" => Some(None),
+            Some(json) => match serde_json::from_str(&json) {
+                Ok(f) => Some(Some(f)),
+                Err(e) => {
+                    return serde_json::json!({"error": format!("invalid gap_filler_json: {e}")})
+                        .to_string()
+                }
+            },
+            None => None,
+        };
         channels::update_channel(
             &self.channel_cmd_deps,
             id,
@@ -122,6 +134,7 @@ impl KTvMcpServer {
             p.timezone,
             p.description,
             schedule_config,
+            gap_filler,
         )
         .await
     }