Crash when navigating log / working set.

**Describe the bug**

Attempted to navigate a git repo, and gitui crashed. See repro steps for description of initial navigation attempts.

PanicHookInfo { payload: Any { .. }, location: Location { file: "asyncgit\\src\\revlog.rs", line: 186, col: 14 }, can_unwind: true, force_no_backtrace: false }
trace:
0: git_odb_object_data
1:
2: git_odb_object_data
3: git_odb_object_data
4: git_odb_object_data
5: git_odb_object_data
6: git_midx_writer_new
7: git_midx_writer_new
8: git_odb_object_data
GitUI was close due to an unexpected panic.
Please file an issue on https://github.com/extrawurst/gitui/issues with the following info:
11: git_midx_writer_new
Any { .. }odb_object_data
trace:git_odb_object_data
0: git_odb_object_data
1: dInitThunk
2: git_odb_object_data
3: git_midx_writer_new
4: git_odb_object_data
5: git_odb_object_data
6: git_odb_object_data
7: BaseThreadInitThunk
8: RtlUserThreadStart

Further attempts to load gitui on the same repo result in an immediate crash.

**To Reproduce**
Steps to reproduce the behavior:

Launched gitui.

Navigated down through changes.
Attempted to select a specific (deleted) file for review.
Encountered crash.

Now when relaunching gitui, encounter crash immediately.

**Expected behavior**
Not crash!

**Screenshots**
Pasted stack trace

**Context (please complete the following information):**
- OS/Distro + Version: [e.g. `macOS 10.15.5`]
- GitUI Version [e.g. `0.5`]
- Rust version: [e.g `1.44`]

- Windows 11 23H2 (OS Build 22631.5624)
- GitUI Version 0.27.0 2025-01-14
- Rust Version: rustc 1.86.0 (05f9846f8 2025-03-31)

Inizia da asyncgit/src/revlog.rs alla riga 186 e riproduci il crash navigando fino a un file eliminato nel working set del repository segnalato. Confronta il primo errore di navigazione con il crash immediato al riavvio, quindi verifica che GitUI non vada più in panic durante il caricamento o la revisione di quel repository.

Scritto dal modello di indicizzazione a partire dal testo della issue.