fix(ci): add baseline CPU variant binaries for legacy hardware support

Closes #2121

bin/platform.d.ts

@@ -0,0 +1,14 @@
+export declare function getPlatformPackage(options: {
+  platform: string;
+  arch: string;
+  libcFamily?: string | null;
+}): string;
+
+export declare function getPlatformPackageCandidates(options: {
+  platform: string;
+  arch: string;
+  libcFamily?: string | null;
+  preferBaseline?: boolean;
+}): string[];
+
+export declare function getBinaryPath(pkg: string, platform: string): string;