Revert `android/CMakeLists.txt` workaround once uniffi-bindgen-react-native > `0.31.0-3` is released

[thunderbiscuit]

uniffi-bindgen-react-native@0.31.0-3 publishes an exports map that does not expose
./package.json:

"exports": {
  ".": {
    "types": "./typescript/dist/esm/index.d.ts",
    "import": "./typescript/dist/esm/index.js",
    "require": "./typescript/dist/cjs/index.js"
  }
}

The generated android/CMakeLists.txt resolves the package root with:

node -p "require.resolve('uniffi-bindgen-react-native/package.json')"

which now throws ERR_PACKAGE_PATH_NOT_EXPORTED. The execute_process call has no
RESULT_VARIABLE, so CMake swallows the failure, UNIFFI_BINDGEN_PATH ends up empty,
and the compile line gets -I/cpp/includes. The build then fails with a misleading:

cpp/generated/bdk.hpp:5:10: fatal error: 'UniffiCallInvoker.h' file n

Why we patched it here rather than in the dependency

Upstream already fixed this by adding "./package.json": "./package.json" to their
exports — jhugman/uniffi-bindgen-react-native#407, merged as `2b57645
unreleased. The latest published version is still 0.31.0-3.

Their CMakeLists template is byte-identical between 0.31.0-3 and main, so there is no
upstream template change to port.

A local patch of the dependency (e.g. pnpm patch) would fix our bui
users': we ship android/CMakeLists.txt inside the tarball and pin 0.31.0-3, so every
downstream consumer resolves the unfixed package from their own `node
has to live in the file we publish.

Pinning the dependency to a git commit on main was also considered and rejected — it
fixes the library build but breaks consumer installs. pnpm 10 refuses
with a prepare script unless allowlisted in pnpm-workspace.yaml, and ubrn's prepare
is yarn build, so every consumer would need yarn on their machine.

What we changed

Commit: fix(android): work around unreleased ubrn package.json export (f6afb0a)

• android/CMakeLists.txt — attempt the stock upstream resolutio
  patch becomes a no-op as soon as they publish, and fall back to walking up from the
  package entry point (which no exports map can gate) when the expo
  Also added the RESULT_VARIABLE guard suggested in the upstream issue, so a failed
  resolution aborts at configure time instead of resurfacing as a mis
• ubrn.config.yaml — added noOverwrite: [android/CMakeLists.txt], because
  ubrn build android --and-generate regenerates that file on every
  otherwise wipe the patch.

Exit criteria

When a uniffi-bindgen-react-native release after 0.31.0-3 is published:

1. Bump the dependency in package.json and the s.dependency version in BdkRn.podspec.
2. Confirm the new version exports ./package.json:
   npm view uniffi-bindgen-react-native@<version> exports --json
3. Revert the commit above (both files).
4. Run just build-tarball-android, confirm android/CMakeLists.txt regenerates cleanly
   now that noOverwrite is gone.
5. Run cd tests && just test against an emulator to confirm the native build still links.

Notes

• Upstream tracking issue: Please cut a release including the package.json exports fix (#407) — Android builds broken for downstream consumers on 0.31.0-3 jhugman/uniffi-bindgen-react-native#421
• Unrelated to this workaround and not to be reverted: 0.31 moved
  runtime to @ubjs/core, which the generated bindings now import, so it had to be added
  to our dependencies. That change stays after the upgrade.