chore(core): set read-only mode on mobile device (#7651)

Close [BS-795](https://linear.app/affine-design/issue/BS-795/affine-mobile-设置只读模式)

- Set read-only mode on mobile device
- Add mobile only support read-only warning toast
- remove `user-select: none` so that user can select text in read-only mode

packages/frontend/core/src/components/top-tip.tsx

@@ -21,11 +21,13 @@ const shouldShowWarning = (() => {
     // disable in SSR
     return false;
   }
+  if (environment.isMobile) {
+    return true;
+  }
   if (environment.isChrome) {
     return environment.chromeVersion < minimumChromeVersion;
-  } else {
-    return !environment.isMobile;
   }
+  return false;
 })();
 
 const OSWarningMessage = () => {
@@ -36,6 +38,11 @@ const OSWarningMessage = () => {
     environment.isChrome &&
     environment.chromeVersion < minimumChromeVersion;
 
+  // TODO(@L-Sun): remove this message when mobile version is able to edit.
+  if ('isMobile' in environment && environment.isMobile) {
+    return <span>{t['com.affine.top-tip.mobile']()}</span>;
+  }
+
   if (notChrome) {
     return (
       <span>
@@ -48,6 +55,7 @@ const OSWarningMessage = () => {
   } else if (notGoodVersion) {
     return <span>{t['upgradeBrowser']()}</span>;
   }
+
   return null;
 };