feat(inbound-form): salamander auto-seed for Hysteria + modernize random buttons

Picking Hysteria from the protocol select used to leave finalmask.udp
empty, so the listener went out without obfs unless the admin added
the salamander wrapper by hand. Hook into onValuesChange so switching
to Hysteria seeds finalmask.udp with
{type: 'salamander', settings: {password: <random>}} alongside the
hysteriaSettings / tlsSettings reset already happening there.

Also modernise the SyncOutlined-in-label "random" affordances on
Shadowsocks password, WireGuard secret key (server + per-peer), and
Reality target / SNI / shortIds into proper icon buttons inside a
Space.Compact next to the field. The old pattern dropped a tiny
clickable icon into the form-item label, which was easy to miss and
inconsistent with the other action buttons in the modal.

frontend/src/components/FinalMaskForm.tsx

@@ -424,8 +424,19 @@ function UdpMaskItem({
           const type = getFieldValue([...absolutePath, 'type']) as string | undefined;
           if (type === 'mkcp-aes128gcm' || type === 'salamander') {
             return (
-              <Form.Item label="Password" name={[fieldName, 'settings', 'password']}>
-                <Input placeholder="Obfuscation password" />
+              <Form.Item label="Password">
+                <Space.Compact block>
+                  <Form.Item name={[fieldName, 'settings', 'password']} noStyle>
+                    <Input placeholder="Obfuscation password" style={{ width: 'calc(100% - 32px)' }} />
+                  </Form.Item>
+                  <Button
+                    icon={<ReloadOutlined />}
+                    onClick={() => form.setFieldValue(
+                      [...absolutePath, 'settings', 'password'],
+                      RandomUtil.randomLowerAndNum(16),
+                    )}
+                  />
+                </Space.Compact>
               </Form.Item>
             );
           }