Add bead separator support to Rosary Builder

- Bead Markers section in library panel with Small, Large, Crucifix cards
- Bead steps render as amber-tinted cards in the sequence (no attribution)
- migrate_v5.php: adds step_type/bead_type columns, makes prayer_id nullable
- Bead steps produce slides with proper bead+bead_index so the ring advances
  during presentation — allows participants to follow along on physical beads
- Prayer steps between beads still show bead_index=null (ring stays on last bead)

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

includes/build_slides.php

@@ -15,9 +15,10 @@ require_once __DIR__ . '/../data/prayers.php';
  */
 function get_builder_steps(PDO $pdo, int $session_id): array {
     $st = $pdo->prepare("
-        SELECT bs.attribution, cp.name, cp.leader_text, cp.all_text
+        SELECT bs.step_type, bs.bead_type, bs.attribution,
+               cp.name, cp.leader_text, cp.all_text
         FROM   builder_steps bs
-        JOIN   custom_prayers cp ON cp.id = bs.prayer_id
+        LEFT   JOIN custom_prayers cp ON cp.id = bs.prayer_id
         WHERE  bs.session_id = ?
         ORDER  BY bs.step_order ASC
     ");
@@ -104,8 +105,25 @@ function build_slides(array $session): array {
             'photo_path' => $session['photo_path'] ?? null,
         ];
 
+        $bead_idx = 0; // increments for each bead separator step
         foreach ($steps as $i => $step) {
-            $attr   = $step['attribution'];
+            $type = $step['step_type'] ?? 'prayer';
+
+            if ($type === 'bead') {
+                $slides[] = [
+                    'id'         => 'bead_' . $i,
+                    'type'       => 'prayer',
+                    'section'    => 'bead',
+                    'title'      => '',
+                    'leader'     => '',
+                    'all'        => '',
+                    'bead'       => $step['bead_type'] ?? 'small',
+                    'bead_index' => $bead_idx++,
+                ];
+                continue;
+            }
+
+            $attr   = $step['attribution'] ?? 'leader_all';
             $leader = '';
             $all    = '';
 
@@ -116,7 +134,6 @@ function build_slides(array $session): array {
                 $all = $step['all_text'] ?? '';
             }
             if ($attr === 'none') {
-                // Show prayer text without attribution labels — put in leader field
                 $leader = ($step['leader_text'] ?: $step['all_text']) ?? '';
             }