[tools] Add apply_patch tool (#2303)

## Summary
We've been seeing a number of issues and reports with our synthetic
`apply_patch` tool, e.g. #802. Let's make this a real tool - in my
anecdotal testing, it's critical for GPT-OSS models, but I'd like to
make it the standard across GPT-5 and codex models as well.

## Testing
- [x] Tested locally
- [x] Integration test

codex-rs/Cargo.lock

@@ -751,6 +751,7 @@ dependencies = [
  "codex-common",
  "codex-core",
  "codex-ollama",
+ "core_test_support",
  "libc",
  "owo-colors",
  "predicates",
@@ -760,6 +761,7 @@ dependencies = [
  "tokio",
  "tracing",
  "tracing-subscriber",
+ "wiremock",
 ]
 
 [[package]]