sendme: fix checkPhase with sandbox=relaxed on Darwin

sendme's tests run the binary, which requires local network access.
sendme also ends up invoking CoreFoundation APIs which require access
to system ICU data. [CoreFoundation will segfault if it cannot access the
system ICU data][1], so add these paths to the sandbox.

[1]: https://gist.github.com/al3xtjames/0897f0d21196276c21d15f5a103f03a0

pkgs/by-name/se/sendme/package.nix

@@ -18,6 +18,15 @@ rustPlatform.buildRustPackage rec {
   useFetchCargoVendor = true;
   cargoHash = "sha256-8Ry3rpGTNcvMIA3Q10Cb3uJHOBQin9AhlLNRekaKw/0=";
 
+  __darwinAllowLocalNetworking = true;
+
+  # On Darwin, sendme invokes CoreFoundation APIs that read ICU data from the
+  # system. Ensure these paths are accessible in the sandbox to avoid segfaults
+  # during checkPhase.
+  sandboxProfile = ''
+    (allow file-read* (subpath "/usr/share/icu"))
+  '';
+
   meta = with lib; {
     description = "Tool to send files and directories, based on iroh";
     homepage = "https://iroh.computer/sendme";