fix: scope Alpine gitea_workspace + commit admin fallback + settings cleanup

1. gitea_workspace.html: owner/repo en Jinja2 dans la topbar (pas Alpine)
2. gitea.py: save_file/delete_file → _require_gitea (admin token can write)
3. settings.html: retrait doublon defaultView, fix workspace_name Jinja2

app/templates/settings.html

@@ -259,22 +259,7 @@
           <div class="setting-row">
             <div>
               <div class="setting-label">Workspace name</div>
-              <div class="setting-desc" x-text="'{{ workspace_name }}'"></div>
-            </div>
-          </div>
-          <div class="setting-row">
-            <div>
-              <div class="setting-label">Default view</div>
-              <div class="setting-desc">Choose the default view for new pages</div>
-            </div>
-            <div class="setting-control">
-              <select class="settings-select" x-model="defaultView" @change="saveDefaultView()">
-                <option value="tree">🌳 Tree</option>
-                <option value="list">📋 List</option>
-                <option value="details">📊 Details</option>
-                <option value="title">🏷️ Cards</option>
-                <option value="content">📝 Content</option>
-              </select>
+              <div class="setting-desc">{{ workspace_name }}</div>
             </div>
           </div>
         </div>