Studio: Reclaim unavailable port after site deletion

package.json

@@ -105,6 +105,7 @@
 		"archiver": "^6.0.1",
 		"compressible": "2.0.18",
 		"compression": "1.7.4",
+		"cross-port-killer": "^1.4.0",
 		"date-fns": "^3.3.1",
 		"electron-squirrel-startup": "^1.0.0",
 		"express": "4.19.2",

src/lib/port-finder.ts

@@ -1,4 +1,5 @@
 import http from 'http';
+import killPort from 'cross-port-killer';
 
 const DEFAULT_PORT = 8881;
 
@@ -72,6 +73,26 @@ class PortFinder {
 			this.#unavailablePorts.push( port );
 		}
 	}
+
+	public reclaimUnavailablePort( port?: number ): void {
+		if ( port && this.#unavailablePorts.includes( port ) ) {
+			killPort( port )
+				.then( () => {
+					console.log( `Killed processes using port ${ port }` );
+				} )
+				.catch( ( err ) => {
+					console.error( `Failed to kill processes using port ${ port }: ${ err.message }` );
+				} )
+				.finally( () => {
+					// Ensure port finder cycles through newly reclaimed ports by removing
+					// from unavailable ports list and resetting #searchPort.
+					this.#unavailablePorts = this.#unavailablePorts.filter(
+						( unavailablePort ) => unavailablePort !== port
+					);
+					this.#searchPort = DEFAULT_PORT;
+				} );
+		}
+	}
 }
 
 export const portFinder = PortFinder.getInstance();

src/site-server.ts

@@ -60,6 +60,7 @@ export class SiteServer {
 		}
 		await this.stop();
 		servers.delete( this.details.id );
+		portFinder.reclaimUnavailablePort( this.details.port );
 	}
 
 	async start() {