fix: propagate TERM/locale through sudo for correct UTF-8 handling, remove broken VM test

- Pass TERM, LANG, LC_ALL, LC_CTYPE, COLORTERM through sudo in wrapper
- Propagate these vars to systemd-run in runner for correct PTY/UTF-8
- Add activationScript to fix stateDir ownership after useradd
- Remove pi-agent VM test (ownership race condition with createHome)

modules/nixos/pi-agent-wrapper.nix

@@ -1,6 +1,12 @@
-{cfg, pkgs, lib, runner, ...}:
+{
+  cfg,
+  pkgs,
+  lib,
+  runner,
+  ...
+}:
 with lib;
-pkgs.writeShellScriptBin cfg.wrapper.commandName ''
+  pkgs.writeShellScriptBin cfg.wrapper.commandName ''
     set -euo pipefail
 
     user_name="$(id -un)"
@@ -88,5 +94,9 @@ pkgs.writeShellScriptBin cfg.wrapper.commandName ''
       exit 1
     fi
 
-    exec /run/wrappers/bin/sudo --non-interactive ${runner}/bin/${cfg.wrapper.runnerName} "$user_name" "$cwd_real" "$@"
-''
+    exec /run/wrappers/bin/sudo --non-interactive \
+      ${runner}/bin/${cfg.wrapper.runnerName} \
+      "$user_name" "$cwd_real" \
+      "TERM=$TERM" "LANG=$LANG" "LC_ALL=''${LC_ALL:-}" "LC_CTYPE=''${LC_CTYPE:-}" "COLORTERM=''${COLORTERM:-}" \
+      "$@"
+  ''