[Bug]: iOS: tapping a bare filename chip like Foo.dm:314 fails when the file is in a subfolder #17830

Before submitting

• I searched existing issues and did not find a duplicate.
• I included enough detail to reproduce or investigate the problem.

Area

apps/mobile

Steps to reproduce

1. Open a project where a file lives in a subfolder, for example src/Example.dm.
2. Get an assistant reply that names the file by bare name with a line number in inline code, like Example.dm:314.
3. Tap the chip in the iOS app.
4. Tap the same chip in the desktop app for comparison.

Expected behavior

The file opens at src/Example.dm, the same as on desktop. Desktop got this in #6297 (fixes #6292): openFileInPanel in apps/web/src/components/ChatMarkdown.tsx asks the workspace index (projects.searchEntries) for an exact basename match before opening. If there is no exact match, the current error is fine.

Actual behavior

iOS shows "File unavailable" / "Failed to read file". The server gets projects.readFile with relativePath Example.dm against the workspace root, and it fails at realpath because there is no such file at the root.

ThreadFileScreen in apps/mobile/src/features/files/ThreadFilesRouteScreen.tsx passes the route path straight to projectEnvironment.readFile. The mobile client has no basename lookup like the one #6297 added on web.

Related but different: #8251 (desktop, slashed paths relative to a subfolder) and #7798 (mobile links outside the workspace, fixed for images and videos only).

Impact

Minor bug or occasional failure

Version or commit

Server 0.0.46-nightly.20261009.2873, iOS app 2.0.0 (114) (TestFlight)

Environment

iOS app connected to a Windows 11 host, Claude provider

Logs or stack traces

ProjectReadFileError: Failed to read workspace file 'Example.dm' in 'C:\dev\project'.

Screenshots, recordings, or supporting files

No response

Workaround

Open the file from the thread's file tree instead of the chip.