Modern tools (rg, fd...)

roles/pi_modern_shell_env/README.md

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+# pi_modern_shell_env
+
+Installs modern CLI tooling (fish, ripgrep, fd, bat, fzf, zoxide, lsd,
+tmux) plus a starship prompt for the login user on `iot` Pi hosts, and
+makes fish the default login shell. Purely a convenience layer for
+interactive SSH sessions into otherwise single-purpose appliance boxes —
+does not affect any of the audio/sensor services these hosts run.
+
+**Key vars:**
+
+- `pi_modern_shell_env_target_user` — user to configure (defaults to
+  `main_user`, falling back to `root`).
+- `pi_modern_shell_env_set_default_shell` — whether to `chsh` the target
+  user to fish (default `true`).