feat(hh): /pw command, RAM-only direnv autostart, robust lets-hack; coven→clergy

- add /pw (alias /password): reveal this room's password locally (never
  broadcast); surfaced in the F1 help overlay and the join hint
- direnv-autostart/: cd-to-launch a single real-user session via direnv;
  password is minted in memory at launch (never written to disk, matching the
  RAM-only model) and scoped to the child process. setup.sh installs direnv,
  hooks bash/zsh, and `direnv allow`s the dir
- lets-hack.sh: boot a FRESH server by default (replacing any live one) with a
  --reuse opt-out; add -h/--help/-help; guard against killing the tmux session
  you're attached to; switch-client into the coven when run inside tmux
- rename coven→clergy across rust/python/scripts; tests/test_coven.py→test_clergy.py
- snapshots in-progress hack-house client work (sandbox, themes, net, ui)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

hh/Cargo.toml

@@ -37,7 +37,7 @@ tar = "0.4"
 tokio = { version = "1", features = ["rt-multi-thread", "macros", "net", "io-util", "sync", "time"] }
 tokio-tungstenite = { version = "0.24", features = ["rustls-tls-webpki-roots"] }
 futures-util = "0.3"
-ratatui = { version = "0.29", features = ["serde"] }
+ratatui = { version = "0.29", features = ["serde", "unstable-rendered-line-info"] }
 crossterm = { version = "0.28", features = ["event-stream"] }
 toml = "0.8"