fix: apply the namespace edits dropped from the task 0031 merge

The task 0031 commit moved the module files but a mis-staged `git add`
left the option-path rewrites out, so main declared the old namespaces
(`modules.claude-code`, `modules.gitea-axi`, `modules.pi`,
`modules.desktop.hyprlock`/`hypridle`) while CONTEXT.md and ADR 0004
already documented the new ones. Rewrite the paths in the moved and
in-place modules, the neogaia host, and the two live CLAUDE.md gotchas
so the code matches the recorded convention.

modules/agents/pi.nix

@@ -7,11 +7,11 @@
 # home-manager, which ships the package and manages ~/.pi/agent.
 # The login credential is left unmanaged, so it survives rebuilds.
 let
-  cfg = config.modules.pi;
+  cfg = config.modules.agents.pi;
   user = config.user.name;
 in
 {
-  options.modules.pi.enable = lib.mkEnableOption ''
+  options.modules.agents.pi.enable = lib.mkEnableOption ''
     Pi, a terminal coding agent, configured via home-manager'';
 
   config = lib.mkIf cfg.enable {