Add AVIF/HEIF/HEIC upload support

client/js/views/post_upload_view.js

@@ -16,6 +16,7 @@ function _mimeTypeToPostType(mimeType) {
             "image/png": "image",
             "image/webp": "image",
             "image/avif": "image",
+            "image/heif": "image",
             "image/heic": "image",
             "video/mp4": "video",
             "video/webm": "video",
@@ -112,6 +113,7 @@ class Url extends Uploadable {
             gif: "image/gif",
             webp: "image/webp",
             avif: "image/avif",
+            heif: "image/heif",
             heic: "image/heic",
             mp4: "video/mp4",
             webm: "video/webm",