Use github.com/<login>.png for GitHub logos

lib/mcp_registry/registry/logo.ex

@@ -114,9 +114,13 @@ defmodule McpRegistry.Registry.Logo do
 
   defp valid_login(_), do: nil
 
-  # avatars.githubusercontent.com answers a login directly with the image, no
-  # redirect -- github.com/<login>.png costs an extra round trip per logo.
-  defp avatar(login), do: "https://avatars.githubusercontent.com/#{login}?size=#{@avatar_px}"
+  # github.com/<login>.png, not the avatars.githubusercontent.com/<login>
+  # shortcut. The shortcut saves a redirect but returns GitHub's grey ghost
+  # placeholder for some organisations -- Microsoft and GitHub both got it --
+  # so on the live grid unrelated listings shared one blank octocat. The
+  # documented form redirects to the real image, and 404s for a login that
+  # does not exist, which lets the monogram show through.
+  defp avatar(login), do: "https://github.com/#{login}.png?size=#{@avatar_px}"
 
   # Lower sorts first. Dark-theme icons last; then SVG; then the smallest
   # raster that is big enough; then any raster; unknown sizes in the middle.

test/mcp_registry/logo_test.exs

@@ -14,19 +14,19 @@ defmodule McpRegistry.Registry.LogoTest do
 
     test "an io.github namespace gets that verified owner's avatar" do
       assert {:github, url} = Logo.for_server(server(%{name: "io.github.troyhunt/hibp"}))
-      assert url == "https://avatars.githubusercontent.com/troyhunt?size=96"
+      assert url == "https://github.com/troyhunt.png?size=96"
     end
 
     test "a domain namespace falls back to its repository owner" do
       s = server(%{repository_url: "https://github.com/cloudflare/mcp-server-cloudflare"})
       assert {:repository, url} = Logo.for_server(s)
-      assert url =~ "/cloudflare?"
+      assert url =~ "/cloudflare.png?"
     end
 
     test "the namespace beats the repository, because only it is verified" do
       s = server(%{name: "io.github.alice/x", repository_url: "https://github.com/bob/x"})
       assert {:github, url} = Logo.for_server(s)
-      assert url =~ "/alice?"
+      assert url =~ "/alice.png?"
     end
 
     test "nothing on the record means no logo, never a guess" do

test/mcp_registry_web/live/server_live_test.exs

@@ -87,7 +87,7 @@ defmodule McpRegistryWeb.ServerLiveTest do
 
       {:ok, _view, html} = live(conn, "/servers/#{server.name}")
 
-      assert html =~ "https://avatars.githubusercontent.com/troyhunt?size=96"
+      assert html =~ "https://github.com/troyhunt.png?size=96"
       # It removes itself if it fails, so the monogram beneath shows instead.
       assert html =~ ~s(onerror="this.remove\(\)")
       assert html =~ ~s(referrerpolicy="no-referrer")
@@ -104,7 +104,7 @@ defmodule McpRegistryWeb.ServerLiveTest do
       {:ok, _view, html} = live(conn, "/servers/#{server.name}")
 
       assert html =~ "https://acme.test/logo.svg"
-      refute html =~ "avatars.githubusercontent.com"
+      refute html =~ "github.com/acme.png"
       assert html =~ "object-contain"
     end
 
@@ -125,7 +125,7 @@ defmodule McpRegistryWeb.ServerLiveTest do
       server_fixture(%{name: "io.github.gridowner/x-#{System.unique_integer([:positive])}"})
       {:ok, _view, html} = live(conn, ~p"/servers")
 
-      assert html =~ "avatars.githubusercontent.com/gridowner"
+      assert html =~ "github.com/gridowner.png"
     end
   end