fix(discover): filter panel as bottom sheet with mask, add debug log

- Changed filter panel from in-flow to fixed bottom drawer with semi-transparent mask
- Mask click closes panel (closeFilterPanel)
- Added console.log in openFilterPanel for debugging event firing
- Panel now z-index:11 above mask z-index:10, guaranteeing visibility

miniapp/pages/discover/discover.ts

@@ -188,6 +188,7 @@ Page({
 
   /** 打开筛选面板，并同步当前 applied 状态到 temp */
   openFilterPanel() {
+    console.log('[discover] openFilterPanel called');
     const a = this.data.applied;
     this.setData({
       showFilter: true,
@@ -196,6 +197,8 @@ Page({
       tempMaxAge: a.maxAge,
       tempEducationCode: a.educationCode,
       tempMaritalStatus: a.maritalStatus,
+    }, () => {
+      console.log('[discover] showFilter set to true, current state:', JSON.stringify(this.data.applied));
     });
   },