Reduce bundle size

Replace @actions/core with local functions

@actions/core is unmaintained and poorly designed for projects that just need basic functions

src/core.ts

@@ -0,0 +1,112 @@
+import {EOL} from 'os';
+
+/**
+ * Commands
+ *
+ * Command Format:
+ *   ::name key=value,key=value::message
+ *
+ * @see https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions
+ */
+
+interface CommandProperties {
+  [key: string]: string;
+}
+
+/**
+ * Sanitizes the message for use in a workflow command.
+ * @param message
+ */
+function toCommandValue(message: string | Error): string {
+  if (message instanceof Error) {
+    return message.toString();
+  }
+  return message;
+}
+
+/**
+ * Escapes data for safe use in workflow command messages.
+ * @param s
+ */
+function escapeData(s: string | Error): string {
+  return toCommandValue(s)
+    .replace(/%/g, '%25')
+    .replace(/\r/g, '%0D')
+    .replace(/\n/g, '%0A');
+}
+
+/**
+ * Escapes property values for safe use in workflow command properties.
+ * @param s
+ */
+function escapeProperty(s: string): string {
+  return s
+    .replace(/%/g, '%25')
+    .replace(/\r/g, '%0D')
+    .replace(/\n/g, '%0A')
+    .replace(/:/g, '%3A')
+    .replace(/,/g, '%2C');
+}
+
+/**
+ * Issues a command to the GitHub Actions runner.
+ *
+ * @param command - The command name to issue
+ * @param properties - Additional properties for the command (key-value pairs)
+ * @param message - The message to include with the command
+ */
+export function issueCommand(
+  command: string,
+  properties: CommandProperties,
+  message: string | Error
+): void {
+  let cmdStr = `::${command}`;
+
+  if (properties && Object.keys(properties).length > 0) {
+    cmdStr += ' ';
+    const props = Object.entries(properties)
+      .filter(([, val]) => val)
+      .map(([key, val]) => `${key}=${escapeProperty(val)}`)
+      .join(',');
+    cmdStr += props;
+  }
+
+  cmdStr += `::${escapeData(message)}`;
+  process.stdout.write(cmdStr + EOL);
+}
+
+/**
+ * Adds an error issue.
+ * @param message - error issue message
+ */
+export function error(message: string | Error): void {
+  issueCommand('error', {}, message);
+}
+
+/**
+ * Sets the action status to failed.
+ * When the action exits it will be with an exit code of 1.
+ * @param message - add error issue message
+ */
+export function setFailed(message: string | Error): void {
+  process.exitCode = 1;
+  error(message);
+}
+
+/**
+ * Gets the value of an input.
+ * The value is trimmed.
+ * Returns an empty string if the value is not defined.
+ *
+ * @param name - name of the input to get
+ * @param required - whether the input is required
+ * @returns string
+ */
+export function getInput(name: string, required = false): string {
+  const val: string =
+    process.env[`INPUT_${name.replace(/ /g, '_').toUpperCase()}`] || '';
+  if (required && !val) {
+    throw new Error(`Input required and not supplied: ${name}`);
+  }
+  return val.trim();
+}