nix: delegate devShell setup to package passthru hooks

- use inputsFrom to inherit build inputs from packages
- concat passthru.devShellHook from each package

nix/devShell.nix

@@ -1,49 +1,26 @@
-# nix/devShell.nix — Fast dev shell with stamp-file optimization
+# nix/devShell.nix — Dev shell that delegates setup to each package
+#
+# Each package in inputsFrom exposes passthru.devShellHook — a bash snippet
+# with stamp-checked setup logic. This file collects and runs them all.
 { inputs, ... }: {
-  perSystem = { pkgs, ... }:
+  perSystem = { pkgs, system, ... }:
     let
-      python = pkgs.python311;
+      hermes-agent = inputs.self.packages.${system}.default;
+      hermes-tui = inputs.self.packages.${system}.tui;
+      packages = [ hermes-agent hermes-tui ];
     in {
       devShells.default = pkgs.mkShell {
+        inputsFrom = packages;
         packages = with pkgs; [
-          python uv nodejs_20 ripgrep git openssh ffmpeg
+          python311 uv nodejs_22 ripgrep git openssh ffmpeg
         ];
 
-        shellHook = ''
+        shellHook = let
+          hooks = map (p: p.passthru.devShellHook or "") packages;
+          combined = pkgs.lib.concatStringsSep "\n" (builtins.filter (h: h != "") hooks);
+        in ''
           echo "Hermes Agent dev shell"
-
+          ${combined}
-          # Composite stamp: changes when nix python or uv change
-          STAMP_VALUE="${python}:${pkgs.uv}"
-          STAMP_FILE=".venv/.nix-stamp"
-
-          # Create venv if missing
-          if [ ! -d .venv ]; then
-            echo "Creating Python 3.11 venv..."
-            uv venv .venv --python ${python}/bin/python3
-          fi
-
-          source .venv/bin/activate
-
-          # Only install if stamp is stale or missing
-          if [ ! -f "$STAMP_FILE" ] || [ "$(cat "$STAMP_FILE")" != "$STAMP_VALUE" ]; then
-            echo "Installing Python dependencies..."
-            uv pip install -e ".[all]"
-            if [ -d mini-swe-agent ]; then
-              uv pip install -e ./mini-swe-agent 2>/dev/null || true
-            fi
-            if [ -d tinker-atropos ]; then
-              uv pip install -e ./tinker-atropos 2>/dev/null || true
-            fi
-
-            # Install npm deps
-            if [ -f package.json ] && [ ! -d node_modules ]; then
-              echo "Installing npm dependencies..."
-              npm install
-            fi
-
-            echo "$STAMP_VALUE" > "$STAMP_FILE"
-          fi
-
           echo "Ready. Run 'hermes' to start."
         '';
       };