fix flutter_rust_bridge_codegen

.gitea/workflows/android.yml

@@ -589,8 +589,8 @@ jobs:
           # Upstream bridge.yml may call the codegen binary through
           # ~/.cargo/bin/... . Our builder intentionally uses a custom
           # CARGO_HOME (for example /opt/rust/cargo), so a hard-coded HOME
-          # cargo path is not portable. The selected tool version has already
-          # been installed above; resolve it through PATH instead.
+          # cargo path is not portable. The preparation script installs the
+          # selected tool version before generation; resolve it through PATH.
           cargo_bin_patterns = (
               r"~/.cargo/bin/flutter_rust_bridge_codegen",
               r"\$HOME/.cargo/bin/flutter_rust_bridge_codegen",
@@ -633,6 +633,9 @@ jobs:
           bash -n bridge-prepare.sh
           bash -n bridge-generate.sh
 
+          # A fresh RAM CARGO_HOME has no preinstalled bridge tools.
+          ./bridge-prepare.sh
+
           echo
           echo "Bridge codegen binary:"
           command -v flutter_rust_bridge_codegen
@@ -643,7 +646,6 @@ jobs:
           grep -n "flutter_rust_bridge_codegen" \
             bridge-generate.sh
 
-          ./bridge-prepare.sh
           ./bridge-generate.sh
 
           test -f src/bridge_generated.rs