feat: expand workspace cache_keys to canned responses and agents

Adds CannedResponse and AccountUser to the per-account cacheable_models so
their cache keys are exposed via /cache_keys and broadcast over ActionCable
on mutation. The endpoint now delegates to Account#cache_keys instead of
listing the three models inline, so future additions only need to touch the
concern.

AccountUser uses bespoke field-gated callbacks rather than the blanket
AccountCacheRevalidator: active_at is bumped on every page navigation and
would otherwise invalidate the agent cache constantly. User adds a
cross-account callback so name/email/display_name/confirmed_at changes
propagate, since those fields appear in the agent serializer but live on
the User model.

app/controllers/api/v1/accounts_controller.rb

@@ -94,11 +94,7 @@ class Api::V1::AccountsController < Api::BaseController
   end
 
   def cache_keys_for_account
-    {
-      label: fetch_value_for_key(params[:id], Label.name.underscore),
-      inbox: fetch_value_for_key(params[:id], Inbox.name.underscore),
-      team: fetch_value_for_key(params[:id], Team.name.underscore)
-    }
+    @account.cache_keys
   end
 
   def fetch_account

app/models/account_user.rb

@@ -36,10 +36,16 @@ class AccountUser < ApplicationRecord
 
   accepts_nested_attributes_for :account
 
+  AGENT_CACHE_RELEVANT_COLUMNS = %w[role availability auto_offline custom_role_id].freeze
+
   after_create_commit :notify_creation, :create_notification_setting
   after_destroy :notify_deletion, :remove_user_from_account
   after_save :update_presence_in_redis, if: :saved_change_to_availability?
 
+  after_commit -> { account.update_cache_key('account_user') }, on: [:create, :destroy]
+  after_update_commit -> { account.update_cache_key('account_user') },
+                      if: -> { saved_changes.keys.intersect?(AGENT_CACHE_RELEVANT_COLUMNS) }
+
   validates :user_id, uniqueness: { scope: :account_id }
 
   def create_notification_setting

app/models/canned_response.rb

@@ -11,6 +11,8 @@
 #
 
 class CannedResponse < ApplicationRecord
+  include AccountCacheRevalidator
+
   validates :content, presence: true
   validates :short_code, presence: true
   validates :account, presence: true

app/models/concerns/cache_keys.rb

@@ -8,7 +8,7 @@ module CacheKeys
 
   included do
     class_attribute :cacheable_models
-    self.cacheable_models = [Label, Inbox, Team]
+    self.cacheable_models = [Label, Inbox, Team, CannedResponse, AccountUser]
   end
 
   def cache_keys

app/models/user.rb

@@ -116,8 +116,12 @@ class User < ApplicationRecord
   has_many :macros, foreign_key: 'created_by_id', inverse_of: :created_by
   # rubocop:enable Rails/HasManyOrHasOneDependent
 
+  AGENT_CACHE_RELEVANT_COLUMNS = %w[name email display_name confirmed_at].freeze
+
   before_validation :set_password_and_uid, on: :create
   after_destroy :remove_macros
+  after_update_commit :bump_account_user_cache_keys,
+                      if: -> { saved_changes.keys.intersect?(AGENT_CACHE_RELEVANT_COLUMNS) }
 
   scope :order_by_full_name, -> { order('lower(name) ASC') }
 
@@ -217,6 +221,10 @@ class User < ApplicationRecord
   def remove_macros
     macros.personal.destroy_all
   end
+
+  def bump_account_user_cache_keys
+    accounts.each { |account| account.update_cache_key('account_user') }
+  end
 end
 
 User.include_mod_with('Audit::User')