LOCK request fails with NotFoundException for paths containing special characters (umlauts) after URL-decoding

[mkonline]

Description

LOCK requests via WebDAV consistently fail with OCP\Files\NotFoundException for file paths containing special characters (German umlauts in our case), even though the file exists and can be read/written normally.

Environment

• Nextcloud version: 34.0.2.1
• files_lock version: 34.0.1
• Client: Nextcloud Desktop Client (mirall) 33.0.5, macOS (arm64)
• PHP: (bitte eure PHP-Version ergänzen)

Steps to reproduce

1. Create/use a file with a special character (umlaut) in the folder or file name, e.g.:
   Projects/_TEAM_BÜRO/___Cover_Letter_Template .docx
2. Open the file via the desktop client (triggers a WebDAV LOCK request)
3. Observe the server log

Expected behavior

The file should be locked successfully, same as for files without special characters.

Actual behavior

Server throws OCP\Files\NotFoundException and the request fails with an uncaught exception. This has been reproduced multiple times, on different files, all with special characters (umlauts) in the path.

Log excerpt

{
  "app": "webdav",
  "method": "LOCK",
  "url": "/remote.php/dav/files/<user>/Projects/_TEAM_B%C3%9CRO/___Cover_Letter_Template%20.docx",
  "message": "/<user>/files/Projects/_TEAM_BÜRO/___Cover_Letter_Template .docx",
  "exception": {
    "Exception": "OCP\\Files\\NotFoundException",
    "Message": "/<user>/files/Projects/_TEAM_BÜRO/___Cover_Letter_Template .docx",
    "Trace": [
      {"file": ".../lib/private/Files/Node/LazyFolder.php", "line": 141, "function": "get", "class": "OC\\Files\\Node\\Root"},
      {"file": ".../apps/files_lock/lib/Service/FileService.php", "line": 119, "function": "get", "class": "OC\\Files\\Node\\LazyFolder"},
      {"file": ".../apps/files_lock/lib/DAV/LockPlugin.php", "line": 192, "function": "getFileFromAbsoluteUri", "class": "OCA\\FilesLock\\Service\\FileService"},
      {"file": ".../3rdparty/sabre/event/lib/WildcardEmitterTrait.php", "line": 89, "function": "httpLock", "class": "OCA\\FilesLock\\DAV\\LockPlugin"}
    ]
  }
}

Additional context

• The file itself opens, edits, and saves correctly outside of the LOCK mechanism (no data loss).
• Only the lock acquisition fails — the practical impact is a missing collision-protection warning when multiple users edit the same file concurrently.
• Reproduced on at least two different files/folders, both containing umlauts (Ü, ö) in the path, suggesting the issue lies in how FileService::getFileFromAbsoluteUri() resolves URL-decoded paths with non-ASCII characters, rather than being specific to one file.