fix: Annotaterb model annotation incomplete migration (#13132)

This pull request fixes the model annotation tooling due to previous
incomplete migration from `annotate` to `annotaterb` gem (#12600). It
also improves the handling of serialized values in the
`InstallationConfig` model by ensuring a default value is set,
simplifying the code, and removing a workaround for YAML
deserialization.

**Annotation tooling updates:**

* Added `.annotaterb.yml` to configure the `annotate_rb` gem with
project-specific options, centralizing annotation settings.
* Replaced the custom `auto_annotate_models.rake` task with the standard
rake task from `annotate_rb`, and added `lib/tasks/annotate_rb.rake` to
load annotation tasks in development environments.
[[1]](diffhunk://#diff-9450d2359e45f1db407b3871dde787a25d60bb721aed179a65ffd2692e95fb4bL1-L61)
[[2]](diffhunk://#diff-578cdfc7ad56637e42472ea891ea286dff8803d9a1750afdbfeafec164d9b8b2R1-R8)

**Model serialization improvements:**

* Updated the `InstallationConfig` model to set a default value for the
`serialized_value` attribute, ensuring it always has a hash with
indifferent access and removing the need for a deserialization
workaround in the `value` method.
[[1]](diffhunk://#diff-b4bdde42c1ad0f584073818bd43dbd865b1b3b50d4701b131979f900d7c68297L22-R22)
[[2]](diffhunk://#diff-b4bdde42c1ad0f584073818bd43dbd865b1b3b50d4701b131979f900d7c68297L36-L39)

---------

Co-authored-by: Sojan Jose <sojan@pepalo.com>

app/models/installation_config.rb

@@ -19,7 +19,7 @@ class InstallationConfig < ApplicationRecord
   # https://discuss.rubyonrails.org/t/cve-2022-32224-possible-rce-escalation-bug-with-serialized-columns-in-active-record/81017
   # FIX ME : fixes breakage of installation config. we need to migrate.
   # Fix configuration in application.rb
-  serialize :serialized_value, coder: YAML, type: ActiveSupport::HashWithIndifferentAccess
+  serialize :serialized_value, coder: YAML, type: ActiveSupport::HashWithIndifferentAccess, default: {}.with_indifferent_access
 
   before_validation :set_lock
   validates :name, presence: true
@@ -33,10 +33,6 @@ class InstallationConfig < ApplicationRecord
   after_commit :clear_cache
 
   def value
-    # This is an extra hack again cause of the YAML serialization, in case of new object initialization in super admin
-    # It was throwing error as the default value of column '{}' was failing in deserialization.
-    return {}.with_indifferent_access if new_record? && @attributes['serialized_value']&.value_before_type_cast == '{}'
-
     serialized_value[:value]
   end