yarn: rely on server for updates

AGENTS.md

@@ -4,7 +4,7 @@
 
 NixOS dotfiles for two hosts using Nix flakes + home-manager:
 - **mreow** — Framework 13 AMD AI 300 laptop, niri WM, greetd, swaylock
-- **yarn** — Desktop, Jovian-NixOS (Steam deck mode), impermanence, sddm, deploy-rs target
+- **yarn** — Desktop, Jovian-NixOS (Steam deck mode), impermanence, sddm, pull-based updates from CI
 
 Secrets in `system/secrets/` and `home-manager/secrets/` are encrypted with git-crypt. **Never read or write files in those directories.**
 
@@ -21,8 +21,10 @@ Secrets in `system/secrets/` and `home-manager/secrets/` are encrypted with git-
 nix build .#nixosConfigurations.mreow.config.system.build.toplevel -L
 nix build .#nixosConfigurations.yarn.config.system.build.toplevel -L
 
-# Remote deploy to yarn via deploy-rs
-deploy .#yarn
+# yarn pulls updates automatically on boot from the binary cache.
+# CI builds the yarn closure, records the store path, and Harmonia serves it.
+# To manually trigger the pull on yarn:
+systemctl start pull-update
 
 # Format all Nix files (uses nixfmt-tree, declared in flake.nix)
 nix fmt