Archive verification info + Embed improvements + Embed Receipts UI (#125)

info panel verification/integrity additions, (fixes on #113)
- info panel: display number of hashes verified valid (and invalid), observer domain (if any), and certificate fingerprint, creation software, and package digest
- info: ensure replayTS is updated, not just replayUrl, to ensure correct stats

404 page: improved formatting on 404 page (via wabac.js)

embeds:
- new embed 'replay-with-info mode, displays replay-only with dropdown showing archival 'receipt, which includes condensed info and verification (hashes valid/invalid, observer domain, cert fingerprint)
- support 'newWindowBase' attribute for specifying base replay URL for opening new window. default: use current url if deepLink enabled, otherwise use https://replayweb.page/
use transparent for embeds
- embed dropdown/receipt styling from @Shrinks99 
- automatically setting noCache and noWebWorker for older browsers (eg. safari < 16)
- add 'hideOffscreen' attribute to enable unloading embed when offscreen

dependencies: update to wabac.js 2.13.0-beta.0

bump version to 1.7.0-beta.0

Embed receipt styling co-authored-by: @Shrinks99

assets/chevron-double-down.svg

@@ -0,0 +1,4 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="currentColor" class="bi bi-chevron-double-down" viewBox="0 0 16 16">
+  <path fill-rule="evenodd" d="M1.646 6.646a.5.5 0 0 1 .708 0L8 12.293l5.646-5.647a.5.5 0 0 1 .708.708l-6 6a.5.5 0 0 1-.708 0l-6-6a.5.5 0 0 1 0-.708z"/>
+  <path fill-rule="evenodd" d="M1.646 2.646a.5.5 0 0 1 .708 0L8 8.293l5.646-5.647a.5.5 0 0 1 .708.708l-6 6a.5.5 0 0 1-.708 0l-6-6a.5.5 0 0 1 0-.708z"/>
+</svg>