Aldus 1.21.0

• Fixed six block validation bugs that caused "invalid block" warnings in the editor: column asymmetric layouts had a flex-basis mismatch when the column order was flipped; group blocks were missing border-radius and box-shadow in the serialised HTML even when those values were set in attributes; media-text blocks were missing the is-vertically-aligned-center class; cover blocks were missing border-radius in the serialised HTML across all cover variants; and media-text and cover-split variants were including spurious wp-image-0 size-full classes on <img> tags without a media ID, which diverged from what WordPress's save function generates.
• Fixed a non-fatal AbortError: Failed to execute 'mapAsync' on 'GPUBuffer' console error that appeared when navigating away from a post while the AI model was still loaded. The error originated inside WebLLM's internal GPU cleanup routine; it is now silenced during engine disposal so it no longer appears as an uncaught rejection.
• The PHP integration CI job now builds plugin assets before running BlockRegistrationTest, fixing an intermittent failure on clean runners where build/block.json was absent.
• Layout cards now stream into the results grid as each response arrives instead of waiting for all styles to finish — the first card typically appears within 1–2 seconds of starting generation.
• Layout descriptions are now generated lazily in the background after the initial cards appear, so the grid is interactive immediately and descriptions fill in as the model catches up.
• Content hint analysis is now fully deterministic (headline length, missing image, missing CTA, long paragraphs, missing quote) — the previous AI model call for this step has been removed, shaving one LLM inference from every generation.
• Layout styles are now pre-filtered by content match before inference runs — styles whose anchor requirements aren't met by the current content mix are skipped, with a "Show more styles" option if you want to see all of them.
• Security hardening: prompt injection framing, schema name whitelist for personality registration, custom_styles key validation, and user ID scoping on all caches.
• State machine fixes: pressing Escape cancels the confirmation screen; stale-results guard prevents a previous generation's results from appearing after a new one starts.
• Theme design system expanded with shadow presets, font family detection, heading font applied across all heading and cover renderers, cover overlay sourced from theme.json, and per-section group block styles.
• PHP backend split into focused files: api-assemble.php, api-config.php, api-health.php, api-telemetry.php, block-register.php, and admin-hooks.php each handle a single concern.
• New integration test suites: BoundaryValueTest (12 cases for edge inputs) and ThemeDesignSystemTest (21 cases for theme colour and shadow helpers).