fix: home-manager module must build term against its own nixpkgs
The module was building the package with the consuming flake's own
`pkgs` argument instead of term's pinned nixpkgs. Caught by actually
building a downstream home-manager profile whose flake follows a
different, newer nixpkgs (nixos-26.05): that nixpkgs's Odin dev
snapshot reorganized core:os (core:os/os2 replaces it, the old core:os
API this codebase uses throughout moved to core:os/old), so the
package failed outright. Fixed by resolving pkgs from
termFlake.inputs.nixpkgs.legacyPackages.${system} instead, so term
always builds with its own known-good Odin regardless of what
nixpkgs the consuming flake happens to use.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KpDBFeBQKx9f5U3pfVeVV3