feat(ios): add share to support (#15340)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
  * Added iOS sharing for URLs, text, web pages, and images.
* Shared content can be reviewed, titled, and saved to an AFFiNE
workspace.
  * Choose destinations including workspaces, tags, and collections.
* Added previews, attachment handling, import status, retry support, and
success/error feedback.
* Pending shares are processed when AFFiNE opens or returns to the
foreground.
* **Bug Fixes**
* Improved workspace profile handling across different workspace types.
* Onboarding completion is now recorded immediately after successful
sign-in verification.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

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Co-authored-by: DarkSky <25152247+darkskygit@users.noreply.github.com>

packages/frontend/apps/ios/App/Shared/ShareInbox/ShareInboxConstants.swift

@@ -0,0 +1,14 @@
+//
+//  ShareInboxConstants.swift
+//  Shared between AFFiNE and ShareExtension
+//
+
+import Foundation
+
+enum ShareInboxConstants {
+  static let appGroupId = "group.app.affine.pro"
+  static let inboxDirectoryName = "ShareInbox"
+  static let attachmentsDirectoryName = "Attachments"
+  static let invalidDirectoryName = "Invalid"
+  static let openInboxURL = URL(string: "affine://share-inbox")!
+}