fix: Loading indicator fixes (#398)

Resolves https://github.com/webrecorder/replayweb.page/issues/397

## Changes

- Uses animated logo when loading
- Show non-animated logo for error and other states where user action is required.
- Only shows progress bar if progress is >0
- Fixes WARC progress bar percentage lagging behind displayed "Loaded"
values
- Fixes "Cancel" not redirecting back to initial view
- Removes extra spacing from logo image file

---------

Co-authored-by: Henry Wilkinson <henry@wilkinson.graphics>
Co-authored-by: Ilya Kreymer <ikreymer@gmail.com>

src/appmain.ts

@@ -403,6 +403,7 @@ export class ReplayWebApp extends LitElement {
       @replay-favicons=${this.onFavIcons}
       @update-title=${this.onTitle}
       @coll-loaded=${this.onCollLoaded}
+      @coll-load-cancel=${this.onCollLoadCancel}
       @about-show=${() => (this.showAbout = true)}
     ></wr-item>`;
   }
@@ -691,6 +692,12 @@ export class ReplayWebApp extends LitElement {
     }
   }
 
+  private onCollLoadCancel() {
+    this.sourceUrl = null;
+    this.loadInfo = null;
+    window.history.pushState({}, "", new URL(window.location.href).origin);
+  }
+
   // @ts-expect-error [// TODO: Fix this the next time the file is edited.] - TS7006 - Parameter 'event' implicitly has an 'any' type.
   onTitle(event) {
     if (event.detail.title) {