[Enhancement] Add download rate limiting to app settings (#646)

* Added rate limit column to settings

* Added limit_rate option to command runner

* Added rate limit to settings form

lib/pinchflat_web/controllers/settings/setting_html/setting_form.html.heex

@@ -47,7 +47,14 @@
         placeholder="0"
         type="number"
         label="Sleep Interval (seconds)"
-        help="Sleep interval in seconds between each extractor request. Must be a positive whole number (or set to 0 to disable)"
+        help="Sleep interval in seconds between each extractor request. Must be a positive whole number. Set to 0 to disable"
+      />
+
+      <.input
+        field={f[:download_throughput_limit]}
+        placeholder="4.2M"
+        label="Download Throughput"
+        help="Sets the max throughput when downloading media. Examples: '50K' or '4.2M'. Leave blank to disable"
       />
     </section>
   </section>