feat(badges): layout CSS system — data-layout attribute, @page injection, style_href

Two compiled layout CSS files in src/lib/ae_events/badges/css/:
  - badge_layout_epson_4x5_fanfold.css — 4"×5" per side, Epson ColorWorks C3500
    fanfold duplex; preferred for general conference use (ISHLT, demos)
  - badge_layout_zebra_zc10l_pvc.css — 3.5"×5.5" PVC card, Zebra ZC10L,
    single-sided (pair with duplex=0 on template)

Rules scoped under [data-layout="..."] on the wrapper — beats Tailwind utility
class specificity without !important. Vite hot-reloads these in dev.

Badge component: add data-layout attribute from template.layout field; import
both layout CSS files (falls back to Tailwind 4"×6" defaults if layout unset).

Print page svelte:head: inject @page paper-size rule per layout code
(@page cannot use attribute selectors so it must be dynamic). Also wire
style_href as a <link> for per-event external client branding CSS.

db_events.ts Badge_template interface: add style_href and duplex fields.
MODULE doc: update layout codes table with badge_4x5_fanfold entry.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/ae_events/badges/css/badge_layout_epson_4x5_fanfold.css

@@ -0,0 +1,42 @@
+/* =============================================================================
+   Badge Layout: Epson ColorWorks C3500/C4000 / ExpoBadge 4" × 5" Fanfold (Duplex)
+   layout code:  badge_4x5_fanfold
+   Badge stock:  4in wide × 5in per side, double-sided, continuous fanfold
+   Used for:     ISHLT, general conference use, preferred demo layout
+
+   Print behavior:
+     Front (5") and back (5") render stacked on screen. When printed, the browser
+     sends a 4" × 10" strip to the Epson ColorWorks driver. @page size is injected
+     dynamically by print/+page.svelte <svelte:head> based on the layout field.
+
+   CSS scope:
+     All rules scoped under [data-layout="badge_4x5_fanfold"] to avoid conflicts
+     with other layouts rendered on the same page. These override the Tailwind
+     utility classes (w-[4in], min-h-[6.0in], etc.) that are hardcoded on the
+     badge sections — attribute + class selectors win over single class selectors.
+   ============================================================================= */
+
+/* --- Badge front --- */
+
+[data-layout="badge_4x5_fanfold"] .badge_front {
+    width: 4in;
+    min-height: 5in;
+    max-height: 5in;
+}
+
+/* Body area: 5in total − ~1in header − ~0.5in footer = ~3.5in for content */
+[data-layout="badge_4x5_fanfold"] .badge_body {
+    max-height: 3.5in;
+}
+
+/* --- Badge back --- */
+
+[data-layout="badge_4x5_fanfold"] .badge_back {
+    width: 4in;
+    min-height: 5in;
+    max-height: 5in;
+}
+
+[data-layout="badge_4x5_fanfold"] .badge_back_content {
+    max-height: 4.5in;
+}

src/lib/ae_events/badges/css/badge_layout_zebra_zc10l_pvc.css

@@ -0,0 +1,29 @@
+/* =============================================================================
+   Badge Layout: Zebra ZC10L — PVC Card 3.5" × 5.5"
+   layout code:  badge_3.5x5.5_pvc
+   Badge stock:  3.5in × 5.5in PVC card (CR80 portrait equivalent)
+   Used for:     Axonius NYC (April 2026), single-sided events
+
+   Print behavior:
+     Single-sided only. Set duplex=0 on the template — the badge_back section
+     will not render at all. @page size (3.5in × 5.5in) is injected dynamically
+     by print/+page.svelte <svelte:head> based on the layout field.
+
+   CSS scope:
+     All rules scoped under [data-layout="badge_3.5x5.5_pvc"] to avoid conflicts.
+     These override the hardcoded Tailwind utility classes on the badge sections.
+   ============================================================================= */
+
+/* --- Badge front --- */
+
+[data-layout="badge_3.5x5.5_pvc"] .badge_front {
+    width: 3.5in;
+    min-height: 5.5in;
+    max-height: 5.5in;
+}
+
+/* Body area: 5.5in total − ~1in header − ~0.5in footer = ~4in for content.
+   Same as the current Tailwind default — no body override needed. */
+
+/* No .badge_back rules — duplex=0 on the template means the back section
+   is not rendered at all (see show_badge_back in ae_comp__badge_obj_view.svelte). */

src/lib/ae_events/db_events.ts

@@ -251,6 +251,8 @@ export interface Badge_template {
 
     layout?: null | string;
     style_filename?: null | string;
+    style_href?: null | string;
+    duplex?: null | number | boolean;
 
     enable?: null | boolean;
     hide?: null | boolean;