enhance(client): Compress non-animated PNG files (#9334)

* style: fix TS lint errors about `ev.target`

* enhance: compress non-animated PNG

* PNG to PNG?

* defer jest things (add it later)

* Delete jest.config.cjs

* check the compressed file size

* log compression stats

* use ??

* handle if ($i == null)

Co-authored-by: tamaina <tamaina@hotmail.co.jp>

yarn.lock

@@ -4975,6 +4975,7 @@ __metadata:
     eventemitter3: 5.0.0
     idb-keyval: 6.2.0
     insert-text-at-cursor: 0.3.0
+    is-file-animated: 1.0.1
     json5: 2.2.1
     katex: 0.15.6
     matter-js: 0.18.0
@@ -9574,6 +9575,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"is-file-animated@npm:1.0.1":
+  version: 1.0.1
+  resolution: "is-file-animated@npm:1.0.1"
+  checksum: bcc281e0694e1ba74adfdef75f83f1637ab6470eceecef867d21b4a98e112c32188514b3172348dd137b82cbe8771b6d683de1439d8e1e86011fed77da896c4e
+  languageName: node
+  linkType: hard
+
 "is-fullwidth-code-point@npm:^1.0.0":
   version: 1.0.0
   resolution: "is-fullwidth-code-point@npm:1.0.0"