chore: configure clippy exported api lint (#653)

Boshen · web-flow · commit d9a3fad3777f · 2026-07-03T07:33:18.000+08:00
Ensures clippy is clean with `avoid-breaking-exported-api = false`.

Validated with `cargo clippy --workspace --all-targets --all-features`.
diff --git a/.clippy.toml b/.clippy.toml
@@ -0,0 +1 @@
+avoid-breaking-exported-api = false
