Revert "Prefer image pastes over HTML in the editor (#2856)"

This reverts commit abd8759d50.

Rolling this back for now, as it's caused a couple of regressions:

- In the old path, we returned (html, internal=False); in the new path,
it's returned as internal=True, which prevents formatting from being
stripped. This requires night mode to reproduce, as we don't strip text
colors in day mode.
- It can result in lost alt tags and filenames, as after right clicking on an
image in Chrome and choosing 'copy image', Chrome puts both the HTML and
the image on the clipboard

Related discussion: https://forums.ankiweb.net/t/anki-23-12-beta/37771/90

qt/aqt/editor.py

@@ -1490,29 +1490,26 @@ class EditorWebView(AnkiWebView):
         # print("urls", mime.urls())
         # print("text", mime.text())
 
+        internal = False
+
         mime = gui_hooks.editor_will_process_mime(
-            mime, self, False, extended, drop_event
+            mime, self, internal, extended, drop_event
         )
 
+        # try various content types in turn
+        if mime.hasHtml():
+            html_content = mime.html()[11:] if internal else mime.html()
+            return html_content, internal
+
         # favour url if it's a local link
         if (
             mime.hasUrls()
             and (urls := mime.urls())
             and urls[0].toString().startswith("file://")
         ):
-            types = (
-                self._processUrls,
-                self._processImage,
-                self._processHtml,
-                self._processText,
-            )
+            types = (self._processUrls, self._processImage, self._processText)
         else:
-            types = (
-                self._processImage,
-                self._processHtml,
-                self._processUrls,
-                self._processText,
-            )
+            types = (self._processImage, self._processUrls, self._processText)
 
         for fn in types:
             html = fn(mime, extended)
@@ -1534,11 +1531,6 @@ class EditorWebView(AnkiWebView):
 
         return buf
 
-    def _processHtml(self, mime: QMimeData, extended: bool = False) -> str | None:
-        if mime.hasHtml():
-            return mime.html()
-        return None
-
     def _processText(self, mime: QMimeData, extended: bool = False) -> str | None:
         if not mime.hasText():
             return None