feat: inline editing for activity mappings (improved UX)

- Edit form now appears at the position of the item being edited
- No scrolling needed - stays at same location
- Matches ActivityPage inline editing behavior
- Visual indicator: Accent border when editing
- Create form still appears at top (separate from list)

Benefits:
- Better UX - no need to scroll to top
- Easier to find edited item after saving
- Consistent with rest of app

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

frontend/src/pages/AdminActivityMappingsPage.jsx

@@ -195,7 +195,6 @@ export default function AdminActivityMappingsPage() {
       </div>
 
       {/* Create new button */}
-      {!editingId && (
       <button
         onClick={startCreate}
         className="btn btn-primary btn-full"
@@ -203,14 +202,11 @@ export default function AdminActivityMappingsPage() {
       >
         <Plus size={16} /> Neues Mapping anlegen
       </button>
-      )}
 
-      {/* Edit form */}
+      {/* New mapping form (only shown when creating) */}
-      {editingId && formData && (
+      {editingId === 'new' && formData && (
-        <div className="card" style={{ padding: 16, marginBottom: 16 }}>
+        <div className="card" style={{ padding: 16, marginBottom: 16, border: '2px solid var(--accent)' }}>
-          <div style={{ fontWeight: 600, marginBottom: 12 }}>
+          <div style={{ fontWeight: 600, marginBottom: 12 }}>➕ Neues Mapping</div>
-            {editingId === 'new' ? '➕ Neues Mapping' : '✏️ Mapping bearbeiten'}
-          </div>
 
           <div style={{ display: 'flex', flexDirection: 'column', gap: 16 }}>
             <div>
@@ -220,8 +216,8 @@ export default function AdminActivityMappingsPage() {
                 value={formData.activity_type}
                 onChange={e => setFormData({ ...formData, activity_type: e.target.value })}
                 placeholder="z.B. Traditionelles Krafttraining"
-                disabled={editingId !== 'new'}
                 style={{ width: '100%' }}
+                autoFocus
               />
               <div style={{ fontSize: 11, color: 'var(--text3)', marginTop: 4 }}>
                 Groß-/Kleinschreibung beachten! Muss exakt mit CSV übereinstimmen.
@@ -289,19 +285,101 @@ export default function AdminActivityMappingsPage() {
         </div>
       )}
 
-      {/* List */}
+      {/* List with inline editing */}
       {mappings.length === 0 ? (
         <div className="card" style={{ padding: 40, textAlign: 'center', color: 'var(--text3)' }}>
           Keine Mappings gefunden
         </div>
       ) : (
         <div style={{ display: 'flex', flexDirection: 'column', gap: 8 }}>
-          {mappings.map(mapping => (
+          {mappings.map(mapping => {
+            const isEditing = editingId === mapping.id
+
+            return (
               <div
                 key={mapping.id}
                 className="card"
-              style={{ padding: 12 }}
+                style={{
+                  padding: 12,
+                  border: isEditing ? '2px solid var(--accent)' : undefined
+                }}
               >
+                {isEditing && formData ? (
+                  /* Inline edit form */
+                  <div>
+                    <div style={{ fontWeight: 600, marginBottom: 12, color: 'var(--accent)' }}>
+                      ✏️ Mapping bearbeiten
+                    </div>
+
+                    <div style={{ display: 'flex', flexDirection: 'column', gap: 12 }}>
+                      <div>
+                        <div className="form-label">Activity Type (nicht änderbar)</div>
+                        <input
+                          className="form-input"
+                          value={formData.activity_type}
+                          disabled
+                          style={{ width: '100%', background: 'var(--surface2)' }}
+                        />
+                      </div>
+
+                      <div>
+                        <div className="form-label">Training Type *</div>
+                        <select
+                          className="form-input"
+                          value={formData.training_type_id}
+                          onChange={e => setFormData({ ...formData, training_type_id: parseInt(e.target.value) })}
+                          style={{ width: '100%' }}
+                        >
+                          {trainingTypes.map(type => (
+                            <option key={type.id} value={type.id}>
+                              {type.icon} {type.name_de} ({type.category})
+                            </option>
+                          ))}
+                        </select>
+                      </div>
+
+                      <div>
+                        <div className="form-label">Profil-ID (leer = global)</div>
+                        <input
+                          className="form-input"
+                          value={formData.profile_id}
+                          onChange={e => setFormData({ ...formData, profile_id: e.target.value })}
+                          placeholder="Leer lassen für globales Mapping"
+                          style={{ width: '100%' }}
+                        />
+                      </div>
+
+                      <div style={{ display: 'flex', gap: 8, marginTop: 8 }}>
+                        <button
+                          onClick={handleSave}
+                          disabled={saving}
+                          className="btn btn-primary"
+                          style={{ flex: 1 }}
+                        >
+                          {saving ? (
+                            <div style={{ display: 'flex', alignItems: 'center', gap: 6, justifyContent: 'center' }}>
+                              <div className="spinner" style={{ width: 14, height: 14 }} />
+                              Speichere...
+                            </div>
+                          ) : (
+                            <>
+                              <Save size={16} /> Speichern
+                            </>
+                          )}
+                        </button>
+                        <button
+                          onClick={cancelEdit}
+                          disabled={saving}
+                          className="btn btn-secondary"
+                          style={{ flex: 1 }}
+                        >
+                          <X size={16} /> Abbrechen
+                        </button>
+                      </div>
+                    </div>
+                  </div>
+                ) : (
+                  /* Normal view */
                   <div style={{
                     display: 'flex',
                     alignItems: 'center',
@@ -346,8 +424,10 @@ export default function AdminActivityMappingsPage() {
                       <Trash2 size={16} />
                     </button>
                   </div>
+                )}
               </div>
-          ))}
+            )
+          })}
         </div>
       )}