feat(web): add public master profiles

Add sanitized public GM profiles with publication controls, public /gm/{slug} pages, and links from public game surfaces.

Bump version -> 3.5.0

src/GmRelay.Web/Components/Pages/Showcase.razor

@@ -130,6 +130,12 @@ else
                     <div class="showcase-card-club">
                         <span>@session.GroupName</span>
                     </div>
+                    @if (!string.IsNullOrWhiteSpace(session.MasterProfileSlug))
+                    {
+                        <div class="showcase-card-master">
+                            <a href="@MasterProfilePath(session.MasterProfileSlug)">@(session.MasterDisplayName ?? "Профиль мастера")</a>
+                        </div>
+                    }
                     <div class="showcase-card-actions">
                         <a class="btn-gm btn-gm-outline" href="@($"/s/{session.Id}")">Подробнее</a>
                         @if (session.AllowDirectRegistration)
@@ -254,7 +260,8 @@ else
 
     .showcase-card-meta,
     .showcase-card-seats,
-    .showcase-card-club {
+    .showcase-card-club,
+    .showcase-card-master {
         font-size: 0.8125rem;
         color: var(--text-secondary);
         font-family: 'Jura', sans-serif;
@@ -264,6 +271,12 @@ else
         color: var(--text-muted);
     }
 
+    .showcase-card-master a {
+        color: var(--accent-primary);
+        text-decoration: none;
+        font-weight: 600;
+    }
+
     .showcase-card-actions {
         margin-top: auto;
         padding-top: 0.75rem;
@@ -428,6 +441,8 @@ else
         return mins > 0 ? $"{hours} ч {mins} мин" : $"{hours} ч";
     }
 
+    private static string MasterProfilePath(string slug) => $"/gm/{slug}";
+
     private static string TranslateFormat(string format) => format switch
     {
         "Online" => "Онлайн",