Transaction rules engine V1 (#1900)

* Domain model sketch

* Scaffold out rules domain

* Migrations

* Remove existing data enrichment for clean slate

* Sketch out business logic and basic tests

* Simplify rule scope building and action executions

* Get generator working again

* Basic implementation + tests

* Remove manual merchant management (rules will replace)

* Revert "Remove manual merchant management (rules will replace)"

This reverts commit 83dcbd9ff0.

* Family and Provider merchants model

* Fix brakeman warnings

* Fix notification loader

* Update notification position

* Add Rule action and condition registries

* Rule form with compound conditions and tests

* Split out notification types, add CTA type

* Rules form builder and Stimulus controller

* Clean up rule registry domain

* Clean up rules stimulus controller

* CTA message for rule when user changes transaction category

* Fix tests

* Lint updates

* Centralize notifications in Notifiable concern

* Implement category rule prompts with auto backoff and option to disable

* Fix layout bug caused by merge conflict

* Initialize rule with correct action for category CTA

* Add rule deletions, get rules working

* Complete dynamic rule form, split Stimulus controllers by resource

* Fix failing tests

* Change test password to avoid chromium conflicts

* Update integration tests

* Centralize all test password references

* Add re-apply rule action

* Rule confirm modal

* Run migrations

* Trigger rule notification after inline category updates

* Clean up rule styles

* Basic attribute locking for rules

* Apply attribute locks on user edits

* Log data enrichments, only apply rules to unlocked attributes

* Fix merge errors

* Additional merge conflict fixes

* Form UI improvements, ignore attribute locks on manual rule application

* Batch AI auto-categorization of transactions

* Auto merchant detection, ai enrichment in batches

* Fix Plaid merchant assignments

* Plaid category matching

* Cleanup 1

* Test cleanup

* Remove stale route

* Fix desktop chat UI issues

* Fix mobile nav styling issues

app/models/rule.rb

@@ -0,0 +1,90 @@
+class Rule < ApplicationRecord
+  UnsupportedResourceTypeError = Class.new(StandardError)
+
+  belongs_to :family
+  has_many :conditions, dependent: :destroy
+  has_many :actions, dependent: :destroy
+
+  accepts_nested_attributes_for :conditions, allow_destroy: true
+  accepts_nested_attributes_for :actions, allow_destroy: true
+
+  validates :resource_type, presence: true
+  validate :no_nested_compound_conditions
+
+  # Every rule must have at least 1 action
+  validate :min_actions
+  validate :no_duplicate_actions
+
+  def action_executors
+    registry.action_executors
+  end
+
+  def condition_filters
+    registry.condition_filters
+  end
+
+  def registry
+    @registry ||= case resource_type
+    when "transaction"
+      Rule::Registry::TransactionResource.new(self)
+    else
+      raise UnsupportedResourceTypeError, "Unsupported resource type: #{resource_type}"
+    end
+  end
+
+  def affected_resource_count
+    matching_resources_scope.count
+  end
+
+  def apply(ignore_attribute_locks: false)
+    actions.each do |action|
+      action.apply(matching_resources_scope, ignore_attribute_locks: ignore_attribute_locks)
+    end
+  end
+
+  def apply_later(ignore_attribute_locks: false)
+    RuleJob.perform_later(self, ignore_attribute_locks: ignore_attribute_locks)
+  end
+
+  private
+    def matching_resources_scope
+      scope = registry.resource_scope
+
+      # 1. Prepare the query with joins required by conditions
+      conditions.each do |condition|
+        scope = condition.prepare(scope)
+      end
+
+      # 2. Apply the conditions to the query
+      conditions.each do |condition|
+        scope = condition.apply(scope)
+      end
+
+      scope
+    end
+
+    def min_actions
+      if actions.reject(&:marked_for_destruction?).empty?
+        errors.add(:base, "must have at least one action")
+      end
+    end
+
+    def no_duplicate_actions
+      action_types = actions.reject(&:marked_for_destruction?).map(&:action_type)
+
+      errors.add(:base, "Rule cannot have duplicate actions #{action_types.inspect}") if action_types.uniq.count != action_types.count
+    end
+
+    # Validation: To keep rules simple and easy to understand, we don't allow nested compound conditions.
+    def no_nested_compound_conditions
+      return true if conditions.none? { |condition| condition.compound? }
+
+      conditions.each do |condition|
+        if condition.compound?
+          if condition.sub_conditions.any? { |sub_condition| sub_condition.compound? }
+            errors.add(:base, "Compound conditions cannot be nested")
+          end
+        end
+      end
+    end
+end