Refine error handling in RequestHandler and the console slightly (#2177)

If we don't explicitly handle random unexpected exceptions, the error
that the front end receives includes a big ole stacktrace, which is
unhelpful for regular users and possibly bad to expose. Instead, we
should provide a vague "something went wrong" message.

Separately, we can create a default SnackBar options and use that (we
want it longer than 1.5 seconds because that's pretty short).

console-webapp/src/app/settings/contact/contact.component.ts

@@ -129,9 +129,7 @@ export class ContactDetailsDialogComponent {
     operationObservable.subscribe({
       complete: this.onCloseCallback.bind(this),
       error: (err: HttpErrorResponse) => {
-        this._snackBar.open(err.error, undefined, {
-          duration: 1500,
-        });
+        this._snackBar.open(err.error);
       },
     });
   }
@@ -175,9 +173,7 @@ export default class ContactComponent {
     if (confirm(`Please confirm contact ${contact.name} delete`)) {
       this.contactService.deleteContact(contact).subscribe({
         error: (err: HttpErrorResponse) => {
-          this._snackBar.open(err.error, undefined, {
-            duration: 1500,
-          });
+          this._snackBar.open(err.error);
         },
       });
     }

console-webapp/src/app/settings/security/security.component.ts

@@ -64,9 +64,7 @@ export default class SecurityComponent {
         this.resetDataSource();
       },
       error: (err: HttpErrorResponse) => {
-        this._snackBar.open(err.error, undefined, {
-          duration: 1500,
-        });
+        this._snackBar.open(err.error);
       },
     });
     this.cancel();

console-webapp/src/app/settings/whois/whois.component.ts

@@ -61,9 +61,8 @@ export default class WhoisComponent {
         this.resetDataSource();
       },
       error: (err: HttpErrorResponse) => {
-        this._snackBar.open(err.error, undefined, {
-          duration: 1500,
-        });
+        this._snackBar.open(err.error);
+        this.loading = false;
       },
     });
     this.cancel();