"/" has an unexpected item type

### Summary

Can't open any existing Vault using Files app

### Please agree to the following

- [x] I have searched [existing issues](https://github.com/cryptomator/ios/issues?q=) for duplicates
- [x] I agree to follow this project's [Code of Conduct](https://github.com/cryptomator/ios/blob/develop/.github/CODE_OF_CONDUCT.md)

### System Setup

- iOS: 26.2 (but I had this happen on previous iOS versions as well)
- iOS Cryptomator app: 2.7.3
- Cryptomator on Windows: 1.18.0

I can't open any Vaults anymore using the Files app (using Nextcloud as a backend). I have tried the Nextcloud "online" mode as well as making the folders available offline via the Nextcloud app. I also have tried creating a test-vault, because I read that Cryptomator on iOS can't deal with old vaults. No luck.

I can't open any existing vault from the iOS Files app, the error is always "/" has an unexpected item type.

I am using the free version right now, so I cannot try out creating a Vault.

### Cloud Type

Other File Provider

### Steps to Reproduce

1. Create new vault using Cryptomator on Windows
2. Create it in Nextcloud
3. Sync Nextcloud to iOS
4. Make folder avaiable offline
5. Check with Files app that folder exists
6. Open **Cryptomator**
7. Click on + > Open Existing Vault
8. iCloud Drive / Other File Provider (error happens in both)
9. Select Vault Folder > Nextcloud > MyVaultFolder
10. Receive error message

### Expected Behavior

Opening of vaults using the iOS Files app works

### Actual Behavior

It doesn't

### Reproducibility

Always

### Relevant Log Output

```shell
2026/01/23 14:41:17:553 Error: itemTypeMismatch(cloudPath: CryptomatorCloudAccessCore.CloudPath(path: "/"))
2026/01/23 14:41:22:938 Error: itemTypeMismatch(cloudPath: CryptomatorCloudAccessCore.CloudPath(path: "/"))
2026/01/23 14:42:51:804 Error: itemTypeMismatch(cloudPath: CryptomatorCloudAccessCore.CloudPath(path: "/"))
2026/01/23 14:57:46:867 Error: itemTypeMismatch(cloudPath: CryptomatorCloudAccessCore.CloudPath(path: "/"))
2026/01/23 14:58:46:658 LocalFileSystemProvider: fillCache(for: /) called with startAccessingSecurityScopedResource: 1
2026/01/23 14:58:46:670 LocalFileSystemProvider: fillCache(for: /) failed readingIntent evaluation with error: itemTypeMismatch
2026/01/23 14:58:46:671 Error: itemTypeMismatch(cloudPath: CryptomatorCloudAccessCore.CloudPath(path: "/"))
2026/01/23 14:58:53:717 Setting trialExpirationDate was removed
2026/01/23 14:58:53:717 Setting fullVersionUnlocked was written with value false
2026/01/23 14:58:53:717 Setting hasRunningSubscription was written with value false
2026/01/23 14:58:56:427 LocalFileSystemProvider: fillCache(for: /) called with startAccessingSecurityScopedResource: 1
2026/01/23 14:58:56:439 LocalFileSystemProvider: fillCache(for: /) failed readingIntent evaluation with error: itemTypeMismatch
2026/01/23 14:58:56:439 Error: itemTypeMismatch(cloudPath: CryptomatorCloudAccessCore.CloudPath(path: "/"))
2026/01/23 14:59:00:899 Setting trialExpirationDate was removed
2026/01/23 14:59:00:899 Setting fullVersionUnlocked was written with value false
2026/01/23 14:59:00:899 Setting hasRunningSubscription was written with value false
```
and one more log in another file
```
2026/01/16 10:09:33:997 enumerator(for: NSFileProviderItemIdentifier(_rawValue: NSFileProviderWorkingSetContainerItemIdentifier)) failed as the extension is not initialized

```
### Anything else?
Looking at the code I can actually find the error message here: https://github.com/cryptomator/ios/blob/d8e9e58b49176cf0df5047b2894979d48ca1e771/FileProviderExtension/FileProviderExtension.swift#L219 and a `// TODO: Change error handling here` 😉

I am assuming, that my way of accessing stuff (Nextcloud > Files app > Cryptomator > iCloud Drive) may not be a supported scenario? I couldn't find any information on this. Accessing the same vaults via Nextclouds WebDAV works.

Start with FileProviderExtension/FileProviderExtension.swift at the linked line 219 and trace the itemTypeMismatch reported for CloudPath "/". Inspect LocalFileSystemProvider.fillCache and its readingIntent evaluation, then reproduce the vault-selection flow with Files and Nextcloud or iCloud Drive. Done means existing vaults can be selected without the unexpected item type error.

Written by the indexing model from the issue text.