Need bump libxev version

[icodesign]

Issue Description

The iOS app will crash when displaying a ghostty surface view.

It's already fixed in mitchellh/libxev#204. We just need update dependency in the main repo.

I've validated using following dependencies:

.libxev = .{
     // mitchellh/libxev
-            .url = "https://deps.files.ghostty.org/libxev-34fa50878aec6e5fa8f532867001ab3c36fae23e.tar.gz",
-            .hash = "libxev-0.0.0-86vtc4IcEwCqEYxEYoN_3KXmc6A9VLcm22aVImfvecYs",
+            .url = "https://github.com/mitchellh/libxev/archive/78781eef639f9eb9935b067b4bbc1e69254bda3d.tar.gz",
+            .hash = "libxev-0.0.0-86vtc3kbEwBykzpSo2s87dYDs1G0fPxn__T4tG5AipAN",
     .lazy = true,
 },
 .vaxis = .{

I can't submit a PR since the dependency by convention is stored in ghostty.org.

Expected Behavior

/

Actual Behavior

/

Reproduction Steps

1. Build iOS app 2. Run the app and it will crash

Ghostty Logs

No response

Ghostty Version

N/A

OS Version Information

macos

(Linux only) Display Server

None

(Linux only) Desktop Environment/Window Manager

No response

Minimal Ghostty Configuration

N/A

Additional Relevant Configuration

No response

I acknowledge that:

• I have reviewed the FAQ and confirm that my issue is NOT among them.
• I have searched the Ghostty repository (both open and closed Discussions and Issues) and confirm this is not a duplicate of an existing issue or discussion.
• I have checked the "Preview" tab on all text fields to ensure that everything looks right, and have wrapped all configuration and code in code blocks with a group of three backticks (```) on separate lines.

[jcollie]

!vouch