[koa-pino-logger] add context variable used for manual logging (#29506)

types/koa-pino-logger/index.d.ts

@@ -26,3 +26,9 @@ declare namespace logger {
         stream?: stream.Writable | stream.Duplex | stream.Transform;
     }
 }
+
+declare module 'koa' {
+    interface Context {
+        log: Logger;
+    }
+}

types/koa-pino-logger/koa-pino-logger-tests.ts

@@ -3,3 +3,8 @@ import logger = require('koa-pino-logger');
 
 const app = new koa();
 app.use(logger());
+
+app.use((ctx) => {
+  ctx.log.info('something else');
+  ctx.body = 'hello world';
+});