chore: Refactor Response Bot Data Schema (#8011)

This PR refactors the schema we introduced in #7518 based on the feedback from production tests. Here is the change log

- Decouple Inbox association to a new table inbox_response_sources -> this lets us share the same response source between multiple inboxes
- Add a status field to responses. This ensures that, by default, responses are created in pending status. You can do quality assurance before making them active. In future, this status can be leveraged by the bot to auto-generate response questions from conversations which require a handoff
- Add response_source association to responses and remove hard dependency from response_documents. This lets users write free-form question answers based on conversations, which doesn't necessarily need a response source.

enterprise/app/dashboards/response_document_dashboard.rb

@@ -38,11 +38,11 @@ class ResponseDocumentDashboard < Administrate::BaseDashboard
   SHOW_PAGE_ATTRIBUTES = %i[
     id
     account
-    content
-    document_id
-    document_link
-    document_type
     response_source
+    document_link
+    document_id
+    document_type
+    content
     created_at
     updated_at
     responses
@@ -53,11 +53,11 @@ class ResponseDocumentDashboard < Administrate::BaseDashboard
   # on the model's form (`new` and `edit`) pages.
   FORM_ATTRIBUTES = %i[
     account
-    content
-    document_id
-    document_link
-    document_type
     response_source
+    document_link
+    document_id
+    document_type
+    content
   ].freeze
 
   # COLLECTION_FILTERS
@@ -70,7 +70,10 @@ class ResponseDocumentDashboard < Administrate::BaseDashboard
   #   COLLECTION_FILTERS = {
   #     open: ->(resources) { resources.where(open: true) }
   #   }.freeze
-  COLLECTION_FILTERS = {}.freeze
+  COLLECTION_FILTERS = {
+    account: ->(resources, attr) { resources.where(account_id: attr) },
+    response_source: ->(resources, attr) { resources.where(response_source_id: attr) }
+  }.freeze
 
   # Overwrite this method to customize how response documents are displayed
   # across all pages of the admin dashboard.