## Description Two problems in the `ReviewRuleForm` and `AgentBasedCriterion` plugin. **1. Hard failure when the AI Agents module is not installed** The `agent_based` criterion type depends on `plugin.manager.ai_agents`, but this dependency is not declared in `ai_content_review.info.yml`. When AI Agents is absent, selecting the criterion type crashes the form with a `ServiceNotFoundException`. Saving or even opening an existing rule with an agent-based criterion also fails. **2. UI text violations of Drupal's interface text standard** Several labels, descriptions, and button labels in the form violate Drupal's interface text standard — wrong entity terminology ("Bundles"), inconsistent capitalisation, jargon-heavy descriptions, missing field descriptions, and button labels that do not follow the paired verb-noun convention. ## Tasks * [x] Guard the form and plugin against a missing `plugin.manager.ai_agents` service: disable the criterion type select with an explanatory message and link, add form validation and save guards. * [x] Fix all UI text violations: entity terminology, capitalisation, button labels, field descriptions, status messages. ## Acceptance criteria * Opening the form without AI Agents installed does not crash. The criterion type select is disabled with a message explaining what to install. * Attempting to save with an agent-based criterion without AI Agents installed shows a clear validation error. * All form labels, descriptions, and messages follow Drupal's interface text standard. ## Testing instructions *(added by implementor before review)* 1. Install `ai_content_review` without `drupal/ai_agents` and open the Add/Edit Review Rule form. Verify no crash and the disabled select with warning message. 2. Install `drupal/ai_agents` and verify the full form works as expected. 3. Visually verify all labels and descriptions match the updated wording.