feat(controller): add read_param_value helper

app/controllers/application_controller.rb

@@ -364,4 +364,20 @@ class ApplicationController < ActionController::Base
   def set_customizable_view_path
     prepend_view_path "app/custom_views"
   end
+
+  # Extract a value from params based on the "path"
+  #
+  # params: { dossiers: { champs_attributes: { 1234 => { value: "hello" } } } }
+  #
+  # Usage: read_param_value("dossiers[champs_attributes][1234]", "value")
+  def read_param_value(path, name)
+    parts = path.split(/\[|\]\[|\]/) + [name]
+    parts.reduce(params) do |value, part|
+      if part.to_i != 0
+        value[part.to_i] || value[part]
+      else
+        value[part]
+      end
+    end
+  end
 end