feat: Migrate crop description to a dedicated column

This change migrates the crop description from the `openfarm_data` JSONB field to a new, dedicated `description` text column in the `crops` table.

A data migration is included to move the existing description data to the new column. The `OpenFarmData` concern is updated to remove the now-redundant `description` method.

app/controllers/crops_controller.rb

@@ -192,6 +192,7 @@ class CropsController < ApplicationController
       :parent_id, :perennial,
       :request_notes, :reason_for_rejection,
       :rejection_notes,
+      :description,
       :row_spacing, :spread, :height,
       :sowing_method, :sun_requirements, :growing_degree_days,
       scientific_names_attributes: %i(scientific_name _destroy id)

app/models/concerns/open_farm_data.rb

@@ -19,10 +19,6 @@ module OpenFarmData
       fetch_attr('tags_array')
     end
 
-    def description
-      fetch_attr('description')
-    end
-
     def common_names
       fetch_attr('common_names')
     end

app/views/crops/_form.html.haml

@@ -42,6 +42,7 @@
         %span.help-block Living more than two years
 
       %h2 OpenFarm Data
+      = f.text_area :description, label: 'Description'
       = f.number_field :row_spacing, label: 'Row Spacing (cm)', min: 0
       = f.number_field :spread, label: 'Spread (cm)', min: 0
       = f.number_field :height, label: 'Height (cm)', min: 0

db/migrate/20251128200506_add_description_to_crops.rb

@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+class AddDescriptionToCrops < ActiveRecord::Migration[7.2]
+  # Temporary model to avoid validation issues
+  class Crop < ApplicationRecord
+  end
+
+  def up
+    add_column :crops, :description, :text
+
+    # Ensure the new column is available to the temporary model
+    Crop.reset_column_information
+
+    Crop.find_each do |crop|
+      next if crop.openfarm_data.blank?
+
+      description = crop.openfarm_data.dig('attributes', 'description')
+      crop.update_column(:description, description) if description.present?
+    end
+  end
+
+  def down
+    remove_column :crops, :description
+  end
+end