feat: permissions (#168)

- Load `app-permissions` from schema exported by `@octokit/openapi`
- Update documentation in README.md
- Implement the `permissions_*` inputs in the action code

---------

Co-authored-by: Parker Brown <17183625+parkerbxyz@users.noreply.github.com>

scripts/update-permission-inputs.js

@@ -0,0 +1,42 @@
+import { readFile, writeFile } from "node:fs/promises";
+
+import OctokitOpenapi from "@octokit/openapi";
+
+const appPermissionsSchema =
+  OctokitOpenapi.schemas["api.github.com"].components.schemas[
+    "app-permissions"
+  ];
+
+await writeFile(
+  `scripts/generated/app-permissions.json`,
+  JSON.stringify(appPermissionsSchema, null, 2) + "\n",
+  "utf8"
+);
+
+const permissionsInputs = Object.entries(appPermissionsSchema.properties)
+  .sort((a, b) => a[0].localeCompare(b[0]))
+  .reduce((result, [key, value]) => {
+    const formatter = new Intl.ListFormat("en", {
+      style: "long",
+      type: "disjunction",
+    });
+    const permissionAccessValues = formatter.format(
+      value.enum.map((p) => `'${p}'`)
+    );
+
+    const description = `${value.description} Can be set to ${permissionAccessValues}.`;
+    return `${result}
+  permission-${key.replace(/_/g, "-")}:
+    description: "${description}"`;
+  }, "");
+
+const actionsYamlContent = await readFile("action.yml", "utf8");
+
+// In the action.yml file, replace the content between the `<START GENERATED PERMISSIONS INPUTS>` and `<END GENERATED PERMISSIONS INPUTS>` comments with the new content
+const updatedActionsYamlContent = actionsYamlContent.replace(
+  /(?<=# <START GENERATED PERMISSIONS INPUTS>)(.|\n)*(?=# <END GENERATED PERMISSIONS INPUTS>)/,
+  permissionsInputs + "\n  "
+);
+
+await writeFile("action.yml", updatedActionsYamlContent, "utf8");
+console.log("Updated action.yml with new permissions inputs");