>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #3591626. --> Reported by: [tim bozeman](https://www.drupal.org/user/2241356) >>> <h4>Backend dispatch system</h4> <p>Introduces <code>BlueprintBackendInterface</code> with a service collector pattern (<code>BlueprintBackendResolver</code>). Backends are checked in priority order; the first returning <code>supports() === TRUE</code> wins. <code>ContentBlueprintBackend</code> (priority -10) handles all fieldable entities as the fallback. This allows <code>entity_blueprint_config</code> to register a higher-priority backend for config entities without modifying the base module.</p> <h4>Context resolver extraction</h4> <p>Extracts the YAML discovery pipeline (universal YAML &rarr; scoped YAML &rarr; hook alter) from <code>BlueprintSchemaBuilder</code> into a standalone <code>BlueprintContextResolver</code> service. Provides point queries for block type context, layout context, and field type guidance without requiring a full schema build. Cached with appropriate tags.</p> <h4>Element resolver</h4> <p>New <code>BlueprintElementResolver</code> service provides unified resolution of any addressable page element by UUID or field name. Returns <code>ResolvedElement</code> value objects enriched with identity, type, current data, guidance, and defaults from context YAML. Supports blocks, paragraphs, fields (on root entity or nested components), sections, and regions.</p> <h4>Deferred operations</h4> <p>New <code>DeferredOperation</code> value object that field handlers can return alongside their immediate values. Signals async work (typed, e.g. <code>image_generation</code>) that must be processed after entity persistence. The consuming module is responsible for dispatching &mdash; entity_blueprint only carries the data.</p> <h4>BlueprintResult expansion</h4> <p>Replaces <code>componentUuids</code> with structured targets: each entry is <code>['uuid' =&gt; ..., 'field_name' =&gt; ...]</code>. Adds deferred targets (subset that should not trigger immediate refresh) and immediate targets (the complement). Carries <code>DeferredOperation[]</code> collected from field handlers. Fluent <code>with*()</code> methods for building up results.</p> <h4>InlineBlockRestrictionChecker</h4> <p>New service that checks <code>layout_builder_restrictions</code> configuration to determine which block types are allowed per section storage and view mode. Used by both schema generation (to filter <code>available_block_types</code>) and <code>addComponent</code> validation.</p> <h4>Layout serializer consolidation</h4> <p>Inline block serialization logic moves from <code>BlueprintSerializer</code> into <code>LayoutSerializer</code> as <code>serializeInlineBlockComponent()</code>. Adds <code>serializeSection()</code> with <code>summarize_blocks</code> mode. <code>LayoutDeserializer</code> refactored for cleaner separation of concerns.</p> <h4>Operations expansion</h4> <p>New <code>updateElement()</code> operation accepts a UUID and flat property bag. Routes properties automatically to the correct storage location: fields on the root entity, fields on an inline block's block_content, managed keys in component configuration, or block label. The AI passes property names and values without needing to understand internal structure.</p> <h4>Field handler manager</h4> <p><code>getHandler()</code> now accepts <code>FieldDefinitionInterface</code> instead of a type string, enabling handlers to make decisions based on field settings, target bundles, and other definition metadata.</p>