docs: fix inaccuracies and add missing required flags in action.yml

action.yml

@@ -15,26 +15,32 @@ inputs:
   debug:
     description: Whether to tell the GitHub client to log details of its requests. true or false. Default is to run in debug mode when the GitHub Actions step debug logging is turned on.
     default: ${{ runner.debug == '1' }}
+    required: false
   user-agent:
-    description: An optional user-agent string
+    description: An optional user-agent string. If the ACTIONS_ORCHESTRATION_ID environment variable is set, it is automatically appended to the user-agent for request tracing.
     default: actions/github-script
+    required: false
   previews:
     description: A comma-separated list of GraphQL API previews to accept
+    required: false
   result-encoding:
-    description: Either "string" or "json" (default "json")—how the result will be encoded
+    description: How the result will be encoded—either "string" (uses String()) or "json" (uses JSON.stringify)
     default: json
+    required: false
   retries:
     description: The number of times to retry a request
     default: "0"
+    required: false
   retry-exempt-status-codes:
     description: A comma separated list of status codes that will NOT be retried e.g. "400,500". No effect unless `retries` is set
     default: 400,401,403,404,422 # from https://github.com/octokit/plugin-retry.js/blob/9a2443746c350b3beedec35cf26e197ea318a261/src/index.ts#L14
+    required: false
   base-url:
     description: An optional GitHub REST API URL to connect to a different GitHub instance. For example, https://my.github-enterprise-server.com/api/v3
     required: false
 outputs:
   result:
-    description: The return value of the script, stringified with `JSON.stringify`
+    description: The return value of the script, encoded as a string. Encoded with `JSON.stringify` when `result-encoding` is `json` (default), or with `String()` when `result-encoding` is `string`.
 runs:
   using: node24
   main: dist/index.js