feat(installer): enhance NixOS installer with SSH access and encryption password input

python/installer/__main__.py

@@ -6,7 +6,7 @@ import curses
 import logging
 import sys
 from argparse import ArgumentParser
-from os import getenv
+from os import environ, getenv
 from pathlib import Path
 from random import getrandbits
 from subprocess import run
@@ -38,6 +38,29 @@ REQUIRED_COMMANDS = (
 )
 
 
+def configure_terminal() -> None:
+    """Force a terminal type every live system has a terminfo entry for.
+
+    Terminals such as kitty advertise TERM values (xterm-kitty) that live
+    systems have no terminfo entry for, so setupterm fails before the TUI
+    can start.
+    """
+    environ["TERM"] = "xterm-256color"
+
+    if getenv("TERMINFO") or getenv("TERMINFO_DIRS"):
+        return
+    terminfo_fallback_directories = (
+        Path("/run/current-system/sw/share/terminfo"),
+        Path("/usr/share/terminfo"),
+        Path("/etc/terminfo"),
+        Path("/lib/terminfo"),
+    )
+
+    existing_directories = [str(directory) for directory in terminfo_fallback_directories if directory.is_dir()]
+    if existing_directories:
+        environ["TERMINFO_DIRS"] = ":".join(existing_directories)
+
+
 def partition_disk(disk: str, swap_size: int, reserve: int = 0) -> None:
     """Partition a disk.
 
@@ -299,8 +322,8 @@ def installer(
                 check=True,
             )
 
-    # Fixed mount point for the new system; the installer runs as root on a fresh disk
-    mnt_dir = "/tmp/nix_install"  # noqa: S108
+    # nixos-install rejects mount points under world-writable paths like /tmp
+    mnt_dir = "/mnt"
 
     Path(mnt_dir).mkdir(parents=True, exist_ok=True)
 
@@ -336,10 +359,14 @@ def main(argv: Sequence[str] | None = None) -> None:
         logger.info("installer runtime dependencies are available")
         return
 
+    configure_terminal()
     state = curses.wrapper(draw_menu)
 
     encrypt_key = getenv("ENCRYPT_KEY")
 
+    if not encrypt_key:
+        encrypt_key = state.encryption_password
+
     if not state.selected_device_ids:
         logger.error("No disks selected; exiting without installing")
         sys.exit(1)