Generate crash report txt and webpage

The last 100 lines of logs are now cached, and when a crash occurs, they
are saved to a file in the temp directory ("/tmp" on *nix), and pretty
HTML version is also created and opened in the browser.
* Currently only handles panics, will be included in more places soon
* Copy button and button to generate a GH issue will be added

css/base.css

@@ -521,3 +521,15 @@ img.img-circle {
     display: flex !important;
     align-items: center;
 }
+
+div.card:contains(section.banner.footer) {
+    padding-bottom: 0px;
+}
+
+.card.sectioned {
+    padding: 0px;
+}
+
+.card.sectioned .section {
+    padding: var(--spacing-4, 1rem);
+}