DetectTunnels (inside every brain_write/brain_update via AutoTunnel) walks with brainfs.WalkRegular and reads titles with ReadRegular: a FIFO under wiki/ no longer hangs the write, and a symlinked note's title no longer becomes a tunnel candidate. A wiki/ that is not a real directory yields no candidates; other walk errors still abort.
Fixes#174. Refs #157 (last reader slice). Adversarial review: BLOCKED, PASS.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: Mathias <mthbqv@gmail.com>