refactor: unify page-icon vertical alignment across all icon types

The page-title icon container used `.flex.self-start` and relied on each
icon type's own intrinsic baseline (font glyph for emoji, SVG bottom
anchor for tabler, etc.), with `margin-top: 8px` and `pb-[1.5px]`
band-aids compensating for one type at a time. Replaced with a single
flex-center 38×38 button rule, scoped to `.ls-page-title .ls-page-icon`,
so every type centers on the same visual axis. Drops the per-type pixel
overrides, the mobile-specific `:size 28` (mobile font is unchanged from
desktop, so the override was a band-aid), and the inline `1lh` style.
Bumps the icon-to-title gap from `gap-2` to `gap-3` (12px) for breathing
room.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/main/frontend/components/block.cljs

@@ -3188,7 +3188,7 @@
                                                (when (ldb/property? block)
                                                  {:type :tabler-icon
                                                   :id "letter-p"})))]
-                        [:div.ls-page-icon.flex.self-start
+                        [:div.ls-page-icon.flex.items-center
                          (icon-component/icon-picker icon
                                                      {:on-chosen (fn [_e icon]
                                                                    (if icon
@@ -3222,18 +3222,12 @@
                                                       :page-title (:block/title block)
                                                       :preview-target-db-id (:db/id block)
                                                       :button-opts (when (:page-title? config)
+                                                                     ;; Drop shui's default sizing/padding so the
+                                                                     ;; CSS rule on .ls-page-title .ls-page-icon
+                                                                     ;; button (38×38 flex-center) takes effect.
                                                                      {:size nil
-                                                                      :class "!p-0.5 !h-auto !w-auto"})
-                                                      :icon-props {:size (cond
-                                                                           (and (util/mobile?) (:page-title? config)) 28
-                                                                           (:page-title? config) 38
-                                                                           :else 20)
-                                                                   :style {:width "1lh"
-                                                                           :height "1lh"
-                                                                           :font-size (cond
-                                                                                        (and (util/mobile?) (:page-title? config)) 24
-                                                                                        (:page-title? config) 38
-                                                                                        :else 18)}}})])))]
+                                                                      :class "!p-0"})
+                                                      :icon-props {:size (if (:page-title? config) 38 20)}})])))]
     [:div.ls-block.swipe-item
      (cond->
       {:id (str "ls-block-"

src/main/frontend/components/block.css

@@ -1141,18 +1141,33 @@ html.is-mac {
   color: var(--rx-gray-09);
 }
 
-.ls-page-title .ls-page-icon svg, .ls-page-title .ls-page-icon button {
+/* Page-title icon container: vertically center the trigger button so the
+   icon optically aligns with the title text. The previous `.self-start`
+   on this element top-aligned the icon, which left every type relying on
+   its own intrinsic baseline (emoji on font baseline, SVG on bottom
+   anchor, etc.) — visible as cross-type misalignment when the hover
+   preview swapped types mid-row. */
+.ls-page-title .ls-page-icon {
+  display: flex;
+  align-items: center;
+}
+
+/* Trigger button: fixed-size flex-center box. All icon types (emoji,
+   tabler, text, avatar, image, image-placeholder) render at :size 38
+   inside this box, so flex-centering puts every type's visual centroid
+   at the box midpoint — uniform vertical anchor regardless of the
+   element's intrinsic baseline. */
+.ls-page-title .ls-page-icon button {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
   width: 38px;
   height: 38px;
 }
 
-/* Image icons in page title - fill the button like avatars do */
-.ls-page-title .ls-page-icon .image-icon {
-  width: 2rem !important; /* 32px, matching avatar size */
-  height: 2rem !important;
-  display: flex;
-  align-items: center;
-  justify-content: center;
+/* Per-type fixups: avatar fallback font size and image asset fill. */
+.ls-page-title .ls-page-icon .ui__avatar span {
+  font-size: 16px;
 }
 
 .ls-page-title .ls-page-icon .image-icon img {
@@ -1161,16 +1176,6 @@ html.is-mac {
   object-fit: contain;
 }
 
-/* Scale up avatars in page title context */
-.ls-page-title .ls-page-icon .ui__avatar {
-  width: 38px;
-  height: 38px;
-}
-
-.ls-page-title .ls-page-icon .ui__avatar span {
-  font-size: 16px;
-}
-
 .ls-page-title .positioned-properties.block-left svg,
 .ls-page-title .positioned-properties.block-right svg {
   width: 24px;
@@ -1212,10 +1217,6 @@ html.is-mac {
     }
 }
 
-.ls-page-title .ls-page-icon button {
-  margin-top: 8px;
-}
-
 .ls-page-title .block-tags {
   @apply relative min-h-full;
 }

src/main/frontend/components/page.css

@@ -68,6 +68,13 @@
     .block-main-container {
       @apply gap-2;
     }
+    /* Icon-to-title spacing in the page-title row. The base
+       `.block-main-content` is `gap-2` (8px) for regular blocks; the
+       page title's icon is bigger (38px box) and benefits from more
+       breathing room — bump to `gap-3` (12px) just here. */
+    .block-main-content {
+      @apply gap-3;
+    }
   }
 
   .edit-input {