docs: replace vague provenance prose with recorded facts

packages/bash/bash-sandbox/src/helpers.ts

@@ -23,7 +23,7 @@ function isUsableWorkdir(path: string): boolean {
 }
 
 /**
- * Attribute only Node ENOENT/EACCES failures with positive argv[0] provenance
+ * Attribute only Node ENOENT/EACCES failures whose error path equals argv[0]
  * after independently ruling out the caller-owned cwd. A supplied error path
  * must exactly identify the runner; without one, the syscall must. With a
  * usable cwd, these codes describe resolution or execute permission for that