feat(frontend): replace placeholder avatar with identicons

i don't actually know what the license on the kitten image is, and while
it's very unlikely, i don't want to get into legal trouble. it was only
ever supposed to be a temporary image, too.

identicons aren't the prettiest but at least they have a clear license
:3

Foxnouns.Frontend/pnpm-lock.yaml

@@ -23,6 +23,9 @@ importers:
       markdown-it:
         specifier: ^14.1.0
         version: 14.1.0
+      minidenticons:
+        specifier: ^4.2.1
+        version: 4.2.1
       pretty-bytes:
         specifier: ^6.1.1
         version: 6.1.1
@@ -1110,6 +1113,10 @@ packages:
     resolution: {integrity: sha512-PXwfBhYu0hBCPw8Dn0E+WDYb7af3dSLVWKi3HGv84IdF4TyFoC0ysxFd0Goxw7nSv4T/PzEJQxsYsEiFCKo2BA==}
     engines: {node: '>=8.6'}
 
+  minidenticons@4.2.1:
+    resolution: {integrity: sha512-oWfFivA0lOx/V/bO/YIJbthB26lV8JXYvhnv9zM2hNd3fzsHTXQ6c6bWZPcvhD3nnOB+lQk/D9lF43BXixrN8g==}
+    engines: {node: '>=15.14.0'}
+
   minimatch@3.1.2:
     resolution: {integrity: sha512-J7p63hRiAjw1NDEww1W7i37+ByIrOWO5XQQAzZ3VOcL0PNybwpfmV/N05zFAzwQ9USyEcX6t3UO+K5aqBQOIHw==}
 
@@ -2369,6 +2376,8 @@ snapshots:
       braces: 3.0.3
       picomatch: 2.3.1
 
+  minidenticons@4.2.1: {}
+
   minimatch@3.1.2:
     dependencies:
       brace-expansion: 1.1.11