refactor: consolidate duplicate utility functions (#12439)

* refactor: consolidate duplicate utility functions

- Add escapeRegExp to src/utils.ts and remove 10 local duplicates
- Rename bash-tools clampNumber to clampWithDefault (different signature)
- Centralize formatError calls to use formatErrorMessage from infra/errors.ts
- Re-export formatErrorMessage from cli/cli-utils.ts to preserve API

* refactor: consolidate remaining escapeRegExp duplicates

* refactor: consolidate sleep, stripAnsi, and clamp duplicates

src/cli/cli-utils.ts

@@ -1,14 +1,13 @@
 import type { Command } from "commander";
+import { formatErrorMessage } from "../infra/errors.js";
+
+export { formatErrorMessage };
 
 export type ManagerLookupResult<T> = {
   manager: T | null;
   error?: string;
 };
 
-export function formatErrorMessage(err: unknown): string {
-  return err instanceof Error ? err.message : String(err);
-}
-
 export async function withManager<T>(params: {
   getManager: () => Promise<ManagerLookupResult<T>>;
   onMissing: (error?: string) => void;