Make Company optional in the UI (frontend-only)

Form labels Company 'optional', client validation no longer flags it
as Required when blank, and the submit handler stubs '(not provided)'
into the payload when the user leaves it empty so the worker's
existing 'company required' contract stays untouched.

Worker, schema, and DB are not changed.

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

Author: backnotprop

apps/marketing/src/pages/workspaces/index.astro

@@ -153,7 +153,9 @@ const teamSizes = [
                 <input type="email" name="email" placeholder="jane@company.com" autocomplete="email" maxlength="320" />
               </div>
               <div class="ws-field">
-                <label class="ws-label">Company</label>
+                <label class="ws-label">
+                  Company <span class="ws-opt">optional</span>
+                </label>
                 <input type="text" name="company" placeholder="Acme Inc." autocomplete="organization" maxlength="160" />
               </div>
             </div>
@@ -475,7 +477,10 @@ const teamSizes = [
         else if (!/^[^\s@]+@[^\s@.]+\.[^\s@]+$/.test(email)) {
           showErr(get('email'), 'Looks invalid'); ok = false;
         }
-        if (!company) { showErr(get('company'), 'Required'); ok = false; }
+        // Company is presented as optional in the UI. The worker still
+        // requires a non-empty value, so stub one here when the user
+        // leaves it blank — keeps the server contract untouched.
+        if (!company) company = '(not provided)';
         if (!team_size) {
           showErr(form.querySelector('[data-field="teamSize"]'), 'Pick one');
           ok = false;