Add command to reload emoji packs from cli for OTP users

Not useful for source releases as we don't have a way to automate connecting to the running instance.

docs/administration/CLI_tasks/emoji.md

@@ -44,3 +44,11 @@ Currently, only .zip archives are recognized as remote pack files and packs are
   The manifest entry will either be written to a newly created `pack_name.json` file (pack name is asked in questions) or appended to the existing one, *replacing* the old pack with the same name if it was in the file previously.
 
   The file list will be written to the file specified previously, *replacing* that file. You _should_ check that the file list doesn't contain anything you don't need in the pack, that is, anything that is not an emoji (the whole pack is downloaded, but only emoji files are extracted).
+
+## Reload emoji packs
+
+```sh tab="OTP"
+./bin/pleroma_ctl emoji reload
+```
+
+This command only works with OTP releases.

lib/mix/tasks/pleroma/emoji.ex

@@ -237,6 +237,12 @@ defmodule Mix.Tasks.Pleroma.Emoji do
     end
   end
 
+  def run(["reload"]) do
+    start_pleroma()
+    Pleroma.Emoji.reload()
+    IO.puts("Emoji packs have been reloaded.")
+  end
+
   defp fetch_and_decode(from) do
     with {:ok, json} <- fetch(from) do
       Jason.decode!(json)