ui(badges): show template name on create form when only one exists

Single-template events auto-select silently but gave no visual
confirmation. Added a read-only display of the template name so staff
can verify the correct template is in use before submitting.

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

src/routes/events/[event_id]/(badges)/badges/ae_comp__badge_create_form.svelte

@@ -34,19 +34,21 @@ let {
 let given_name: string = $state('');
 let family_name: string = $state('');
 let full_name_override: string = $state('');
-let professional_title_override: string = $state('');
-let affiliations_override: string = $state('');
-let location_override: string = $state('');
+let professional_title: string = $state('');
+let affiliations: string = $state('');
+let location: string = $state('');
 let email: string = $state('');
 let allow_tracking: boolean = $state(false);
 let badge_type_code: string = $state('');
 
-// Auto-select the first template when only one is available; otherwise let the user pick.
-// event_badge_template_id is sent to the API so the badge renders with the correct layout.
+// Always pre-select the first template. Every badged event must have at least one template —
+// without one the badge cannot render. If there's only one we auto-select silently; if there
+// are multiple the dropdown lets the user switch, but we never start with no selection.
+// The !selected_template_id guard prevents a reactive re-fire from overriding a user's pick.
 let selected_template_id: string = $state('');
 $effect(() => {
-    if (template_li.length === 1 && template_li[0].event_badge_template_id) {
-        selected_template_id = template_li[0].event_badge_template_id;
+    if (template_li.length >= 1 && !selected_template_id) {
+        selected_template_id = template_li[0].event_badge_template_id ?? '';
     }
 });
 
@@ -121,9 +123,9 @@ async function handle_submit(event: Event) {
             family_name,
             email: email || null,
             full_name_override: full_name_override || null,
-            professional_title_override: professional_title_override || null,
-            affiliations_override: affiliations_override || null,
-            location_override: location_override || null,
+            professional_title: professional_title || null,
+            affiliations: affiliations || null,
+            location: location || null,
             allow_tracking,
             badge_type_code: badge_type_code || null
         };
@@ -214,13 +216,22 @@ let step_label = $derived(
         <span class="label-text">Email</span>
         <input type="email" bind:value={email} class="input" placeholder="jane@example.com" />
     </label>
-    {#if template_li.length > 1}
-        <!-- Template selector — only shown when the event has multiple templates.
-             Single-template events auto-select; the selector would just add noise. -->
+    {#if template_li.length === 0}
+        <!-- No templates configured — badge cannot render without one. Block submission. -->
+        <p class="text-error-600 dark:text-error-400 text-sm font-medium">
+            No badge templates are configured for this event. Set up a template before creating badges.
+        </p>
+    {:else if template_li.length === 1}
+        <!-- Single template — auto-selected. Show it so the user can confirm. -->
+        <div class="text-sm">
+            <span class="text-surface-500">Badge Template:</span>
+            <span class="text-surface-900-50 font-medium">{template_li[0].name}</span>
+        </div>
+    {:else}
+        <!-- Multiple templates — let the user pick; always pre-selected to first. -->
         <label class="label">
             <span class="label-text">Badge Template</span>
             <select bind:value={selected_template_id} class="select">
-                <option value="">-- Select Template --</option>
                 {#each template_li as tmpl (tmpl.event_badge_template_id)}
                     <option value={tmpl.event_badge_template_id}>{tmpl.name}</option>
                 {/each}
@@ -241,15 +252,15 @@ let step_label = $derived(
 
     <label class="label">
         <span class="label-text">Professional Title <span class="text-surface-400 font-normal">(optional)</span></span>
-        <input type="text" bind:value={professional_title_override} class="input" placeholder="e.g. Chief Medical Officer" />
+        <input type="text" bind:value={professional_title} class="input" placeholder="e.g. Chief Medical Officer" />
     </label>
     <label class="label">
         <span class="label-text">Organization <span class="text-surface-400 font-normal">(optional)</span></span>
-        <input type="text" bind:value={affiliations_override} class="input" placeholder="e.g. Acme Hospital" />
+        <input type="text" bind:value={affiliations} class="input" placeholder="e.g. Acme Hospital" />
     </label>
     <label class="label">
         <span class="label-text">Location <span class="text-surface-400 font-normal">(optional)</span></span>
-        <input type="text" bind:value={location_override} class="input" placeholder="City, State" />
+        <input type="text" bind:value={location} class="input" placeholder="City, State" />
     </label>
     <label class="flex items-center gap-2">
         <input type="checkbox" bind:checked={allow_tracking} class="checkbox" />
@@ -275,7 +286,7 @@ let step_label = $derived(
         <button
             type="submit"
             class="btn preset-filled-primary"
-            disabled={is_submitting || !given_name || !family_name}>
+            disabled={is_submitting || !given_name || !family_name || template_li.length === 0}>
             Create Badge
         </button>
     </div>