Fix #5082: NoMethodError when searching an old-style dead fanbox url in artist urls.

This API call:

    # profile: https://www.pixiv.net/fanbox/creator/40684196
    curl -H "Origin: https://fanbox.cc" "https://api.fanbox.cc/creator.get?userId=40684196"

returns `{ "body": nil }` when the artist is deleted. We didn't expect `body` to be nil.

Also fix it so that `profile_url` returns the `https://www.pixiv.net/fanbox/creator/40684196`
URL if we can't get the `https://<username>.fanbox.cc` URL, usually because the API call failed
because the artist is deleted.

app/logical/source/extractor/fanbox.rb

@@ -35,17 +35,19 @@ module Source
       end
 
       def profile_url
-        return if artist_name.blank?
-
-        "https://#{artist_name}.fanbox.cc"
+        if artist_name.present?
+          "https://#{artist_name}.fanbox.cc"
+        elsif artist_id_from_url.present?
+          "https://www.pixiv.net/fanbox/creator/#{artist_id_from_url}"
+        end
       end
 
       def artist_name
-        artist_name_from_url || api_response["creatorId"] || artist_api_response["creatorId"]
+        artist_name_from_url || api_response["creatorId"] || artist_api_response.dig("body", "creatorId")
       end
 
       def display_name
-        api_response.dig("user", "name") || artist_api_response.dig("user", "name")
+        api_response.dig("user", "name") || artist_api_response.dig("body", "user", "name")
       end
 
       def other_names
@@ -110,10 +112,11 @@ module Source
       def artist_api_response
         # Needed to fetch artist from cover pages
         return {} if artist_id_from_url.blank?
+
         resp = client.get("https://api.fanbox.cc/creator.get?userId=#{artist_id_from_url}")
-        JSON.parse(resp)["body"]
-      rescue JSON::ParserError
-        {}
+        return {} if resp.status != 200
+
+        resp.parse
       end
 
       def client

test/unit/sources/fanbox_test.rb

@@ -135,6 +135,15 @@ module Sources
       end
     end
 
+    context "A deleted /fanbox/creator/:id profile url" do
+      should "not raise an exception" do
+        source = Source::Extractor.find("https://www.pixiv.net/fanbox/creator/40684196")
+
+        assert_equal("https://www.pixiv.net/fanbox/creator/40684196", source.profile_url)
+        assert_nothing_raised { source.to_h }
+      end
+    end
+
     context "generating page urls" do
       should "convert cover images to the profile url" do
         cover = "https://pixiv.pximg.net/c/400x400_90_a2_g5/fanbox/public/images/creator/1566167/profile/Ix6bnJmTaOAFZhXHLbWyIY1e.jpeg"