fix(wizard): editable slug on confirm step so slug_taken (409) is fixable in place

POST /v1/servers returns 409 slug_taken when the org already has that slug. The error told users to change the slug field above, but the normal (non-fork) flow had no slug field on the confirm step - only Step 1 did - leaving them stuck. Now Name+Slug are editable on the confirm step for the normal flow too, mirroring the fork flow, so a slug conflict is resolved without going back.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/web/app/(dashboard)/servers/new/page.tsx

@@ -616,6 +616,31 @@ function NewServerPageInner() {
               </div>
             </div>
           )}
+          {!forkedTemplateTitle && (
+            <div className="grid gap-3 md:grid-cols-2">
+              <div className="space-y-1.5">
+                <Label htmlFor="confirm-name">Name</Label>
+                <Input
+                  id="confirm-name"
+                  value={name}
+                  onChange={(e) => {
+                    setName(e.target.value);
+                    if (!slug || slug === trySlug(name)) setSlug(trySlug(e.target.value));
+                  }}
+                />
+              </div>
+              <div className="space-y-1.5">
+                <Label htmlFor="confirm-slug" hint="must be unique in your workspace · part of the URL">
+                  Slug
+                </Label>
+                <Input
+                  id="confirm-slug"
+                  value={slug}
+                  onChange={(e) => setSlug(trySlug(e.target.value))}
+                />
+              </div>
+            </div>
+          )}
           <div className="panel p-4">
             <div className="flex items-baseline justify-between">
               <h2 className="text-[14px] font-semibold tracking-tight">