fix(ios): force fmt to c++17 for Xcode 26

[samholmes]

Newer Apple Clang toolchains fail to compile fmt 11.0.2 under C++20 with consteval-related errors, blocking simulator builds on Xcode 26.

Keep the workaround in Podfile post_install so pod regeneration consistently reapplies FMT_USE_CONSTEVAL=0 and fmt-specific C++17 settings instead of requiring manual edits in Pods/.

CHANGELOG

Does this branch warrant an entry to the CHANGELOG?

• Yes
• No

Dependencies

none

Requirements

If you have made any visual changes to the GUI. Make sure you have:

• Tested on iOS device
• Tested on Android device
• Tested on small-screen device (iPod Touch)
• Tested on large-screen device (tablet)

---

Note

Medium Risk
Touches iOS CocoaPods post_install build settings and forces C++ flags, which could affect native pod compilation/linking across configs even though it’s a targeted workaround.

Overview
Keeps Xcode simulator/device builds working on newer Apple Clang toolchains by adding CocoaPods post_install overrides for the fmt dependency.

This globally adds FMT_USE_CONSTEVAL=0 to pod preprocessor definitions, and after react_native_post_install re-applies fmt-specific C++17 settings (including updating generated .xcconfig values) so the workaround persists across pod install regenerations.

Updates Podfile.lock checksum accordingly.

^{Reviewed by Cursor Bugbot for commit 1394f3d. Bugbot is set up for automated code reviews on this repo. Configure here.}

---

• To see the specific tasks where the Asana app for GitHub is being used, see below:
  • https://app.asana.com/0/0/1214132729916516
  • https://app.asana.com/0/0/1213922250562666

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit f4e8c87. Configure here.}

[j0ntz]

Attempt to find a future proof solution for post RN upgrade. If not possible, just merge

[j0ntz]

Check last comment