refactor(action): simplify composite action structure

- Replaces custom with-post-step logic with Node.js-based implementation
- Consolidates main and post scripts for clarity and maintainability
- Updates descriptions and input definitions for improved readability

dist/post.js

@@ -0,0 +1,31 @@
+const cp = require("child_process");
+const path = require("path");
+
+function run(script, args = []) {
+  cp.execFileSync(script, {
+    stdio: "inherit",
+    shell: true,
+    env: process.env,
+  });
+}
+
+function main() {
+  const actionPath = process.env.GITHUB_ACTION_PATH || ".";
+  const versionChanged = (process.env.VERSION_CHANGED || "false").toLowerCase() === "true";
+
+  const readCliff = path.join(actionPath, "scripts/read-cliff-version.sh");
+  const cliffVersion = cp.execSync(readCliff, { encoding: "utf-8", shell: true }).trim().split("\n").pop();
+
+  run(path.join(actionPath, "scripts/install-git-cliff.sh"), [cliffVersion]);
+
+  run(`${path.join(actionPath, "scripts/setup-git.sh")} "${process.env.INPUT_AUTHOR_NAME}" "${process.env.INPUT_AUTHOR_EMAIL}"`);
+
+  if (versionChanged) {
+    process.env.RELEASE_PUBLISH_TOKEN = process.env.INPUT_TOKEN || "";
+    run(path.join(actionPath, "scripts/release-from-version.sh"));
+  } else {
+    run(path.join(actionPath, "scripts/generate-unreleased-changelog.sh"));
+  }
+}
+
+main();