timeline controller: rate limit timelines to 3 requests per 500ms per timeline per ip/user

config/config.exs

@@ -599,6 +599,7 @@ config :http_signatures,
 
 config :pleroma, :rate_limit,
   authentication: {60_000, 15},
+  timeline: {500, 3},
   search: [{1000, 10}, {1000, 30}],
   app_account_creation: {1_800_000, 25},
   relations_actions: {10_000, 10},

config/description.exs

@@ -2465,6 +2465,12 @@ config :pleroma, :config_description, [
         description: "For the search requests (account & status search etc.)",
         suggestions: [{1000, 10}, [{10_000, 10}, {10_000, 50}]]
       },
+      %{
+        key: :timeline,
+        type: [:tuple, {:list, :tuple}],
+        description: "For requests to timelines (each timeline has it's own limiter)",
+        suggestions: [{1000, 10}, [{10_000, 10}, {10_000, 50}]]
+      },
       %{
         key: :app_account_creation,
         type: [:tuple, {:list, :tuple}],