Extract test modules to separate files
Move #[cfg(test)] blocks from 6 large source files into sibling
*_tests.rs files using #[path] attributes. No behavioral changes —
all 252 tests pass unchanged.
Files split:
- config.rs → config_tests.rs (281 lines)
- xrpc.rs → xrpc_tests.rs (312 lines)
- download_keyring.rs → download_keyring_tests.rs (395 lines)
- did.rs → did_tests.rs (217 lines)
- crypto.rs → crypto_tests.rs (207 lines)
- remove_member.rs → remove_member_tests.rs (155 lines)