proxy-backend: cleaner and more informative log messages

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

.changeset/neat-laws-hide.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-proxy-backend': patch
+---
+
+Clean up proxy creation log messages and make them include the mount path.

plugins/proxy-backend/src/service/router.ts

@@ -148,6 +148,8 @@ export function buildMiddleware(
 
     return fullConfig?.allowedMethods?.includes(req.method!) ?? true;
   };
+  // Makes http-proxy-middleware logs look nicer and include the mount path
+  filter.toString = () => route;
 
   // Only forward the allowed HTTP headers to not forward unwanted secret headers
   const responseHeaderAllowList = new Set<string>(