feat: add @automaker/utils package

- Extract error handling utilities (isAbortError, classifyError, etc.)
- Extract conversation utilities (formatHistoryAsText, etc.)
- Extract image handling utilities (readImageAsBase64, etc.)
- Extract prompt building utilities (buildPromptWithImages)
- Extract logger utilities (createLogger, setLogLevel)
- Extract file system utilities (mkdirSafe, existsSafe)

All utilities now use @automaker/types for type imports.
Provides shared utility functions for both server and UI.

Dependencies: @automaker/types

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

libs/utils/src/logger.ts

@@ -0,0 +1,74 @@
+/**
+ * Simple logger utility with log levels
+ * Configure via LOG_LEVEL environment variable: error, warn, info, debug
+ * Defaults to 'info' if not set
+ */
+
+export enum LogLevel {
+  ERROR = 0,
+  WARN = 1,
+  INFO = 2,
+  DEBUG = 3,
+}
+
+const LOG_LEVEL_NAMES: Record<string, LogLevel> = {
+  error: LogLevel.ERROR,
+  warn: LogLevel.WARN,
+  info: LogLevel.INFO,
+  debug: LogLevel.DEBUG,
+};
+
+let currentLogLevel: LogLevel = LogLevel.INFO;
+
+// Initialize log level from environment variable
+const envLogLevel = process.env.LOG_LEVEL?.toLowerCase();
+if (envLogLevel && LOG_LEVEL_NAMES[envLogLevel] !== undefined) {
+  currentLogLevel = LOG_LEVEL_NAMES[envLogLevel];
+}
+
+/**
+ * Create a logger instance with a context prefix
+ */
+export function createLogger(context: string) {
+  const prefix = `[${context}]`;
+
+  return {
+    error: (...args: unknown[]): void => {
+      if (currentLogLevel >= LogLevel.ERROR) {
+        console.error(prefix, ...args);
+      }
+    },
+
+    warn: (...args: unknown[]): void => {
+      if (currentLogLevel >= LogLevel.WARN) {
+        console.warn(prefix, ...args);
+      }
+    },
+
+    info: (...args: unknown[]): void => {
+      if (currentLogLevel >= LogLevel.INFO) {
+        console.log(prefix, ...args);
+      }
+    },
+
+    debug: (...args: unknown[]): void => {
+      if (currentLogLevel >= LogLevel.DEBUG) {
+        console.log(prefix, "[DEBUG]", ...args);
+      }
+    },
+  };
+}
+
+/**
+ * Get the current log level
+ */
+export function getLogLevel(): LogLevel {
+  return currentLogLevel;
+}
+
+/**
+ * Set the log level programmatically (useful for testing)
+ */
+export function setLogLevel(level: LogLevel): void {
+  currentLogLevel = level;
+}