Remove bulk product update functionality

Removes the bulk product update feature and its associated components:
- Removes Angular-based bulk product editing controller and views
- Deletes bulk product API endpoints and related controller actions
- Removes product cloning and variant deletion functionality
- Removes associated JavaScript tests and specs

This appears to be part of a larger effort to modernize/simplify the product management interface, removing legacy Angular-based bulk editing in favor of a different approach.

app/assets/javascripts/admin/services/bulk_products.js.coffee

@@ -1,76 +0,0 @@
-angular.module("ofn.admin").factory "BulkProducts", (ProductResource, dataFetcher, $http) ->
-  new class BulkProducts
-    products: []
-    pagination: {}
-
-    fetch: (params) ->
-      ProductResource.index params, (data) =>
-        @products.length = 0
-        @addProducts data.products
-        angular.extend(@pagination, data.pagination)
-
-    cloneProduct: (product) ->
-      $http.post("/api/v0/products/" + product.id + "/clone").then (response) =>
-        dataFetcher("/api/v0/products/" + response.data.id + "?template=bulk_show").then (newProduct) =>
-          @unpackProduct newProduct
-          @insertProductAfter(product, newProduct)
-
-    updateVariantLists: (serverProducts) ->
-      for server_product in serverProducts
-        product = @findProductInList(server_product.id, @products)
-        product.variants = server_product.variants
-        @loadVariantUnitValues product.variants
-
-    find: (id) ->
-      @findProductInList id, @products
-
-    findProductInList: (id, product_list) ->
-      products = (product for product in product_list when product.id == id)
-      if products.length == 0 then null else products[0]
-
-    addProducts: (products) ->
-      for product in products
-        @unpackProduct product
-        @products.push product
-
-    insertProductAfter: (product, newProduct) ->
-      index = @products.indexOf(product)
-      @products.splice(index + 1, 0, newProduct)
-
-    unpackProduct: (product) ->
-      @loadVariantUnit product
-
-    loadVariantUnit: (product) ->
-      @loadVariantUnitValues product.variants if product.variants
-
-    loadVariantUnitValues: (variants) ->
-      for variant in variants
-        @loadVariantUnitValue variant
-
-    loadVariantUnitValue: (variant) ->
-      variant.variant_unit_with_scale =
-        if variant.variant_unit && variant.variant_unit_scale && variant.variant_unit != 'items'
-          "#{variant.variant_unit}_#{variant.variant_unit_scale}"
-        else if variant.variant_unit
-          variant.variant_unit
-        else
-          null
-
-      unit_value = @variantUnitValue variant
-      unit_value = if unit_value? then unit_value else ''
-      variant.unit_value_with_description = "#{unit_value} #{variant.unit_description || ''}".trim()
-
-    variantUnitValue: (variant) ->
-      if variant.unit_value?
-        if variant.variant_unit_scale
-          variant_unit_value = @divideAsInteger variant.unit_value, variant.variant_unit_scale
-          parseFloat(window.bigDecimal.round(variant_unit_value, 2))
-        else
-          variant.unit_value
-      else
-        null
-
-    # forces integer division to avoid javascript floating point imprecision
-    # using one billion as the multiplier so that it works for numbers with up to 9 decimal places
-    divideAsInteger: (a, b) ->
-      (a * 1000000000) / (b * 1000000000)