fix(flake.nix): synchronize playwright version in nix and package.json (#16715)

Ensure that the version of Playwright installed with the Nix flake is
equal to the one specified in `site/package.json.` -- This assertion
ensures that `pnpm playwright:install` will not attempt to download
newer browser versions not present in the Nix image, fixing the startup
script and reducing the startup time, as `pnpm playwright:install` will
not download or install anything.

We also pre-install the required Playwright web browsers in the dogfood
Dockerfile. This change prevents us from redownloading system
dependencies and Google Chrome each time a workspace starts.

Change-Id: I8cc78e842f7d0b1d2a90a4517a186a03636c5559
Signed-off-by: Thomas Kosiewski <tk@coder.com>

Signed-off-by: Thomas Kosiewski <tk@coder.com>

flake.nix

@@ -121,6 +121,7 @@
             (pinnedPkgs.golangci-lint)
             gopls
             gotestsum
+            hadolint
             jq
             kubectl
             kubectx
@@ -216,6 +217,14 @@
             '';
           };
       in
+      # "Keep in mind that you need to use the same version of playwright in your node playwright project as in your nixpkgs, or else playwright will try to use browsers versions that aren't installed!"
+      # - https://nixos.wiki/wiki/Playwright
+      assert pkgs.lib.assertMsg
+        (
+          (pkgs.lib.importJSON ./site/package.json).devDependencies."@playwright/test"
+          == pkgs.playwright-driver.version
+        )
+        "There is a mismatch between the playwright versions in the ./nix.flake and the ./site/package.json file. Please make sure that they use the exact same version.";
       rec {
         inherit formatter;
 
@@ -261,12 +270,13 @@
 
               uname = "coder";
               homeDirectory = "/home/${uname}";
+              releaseName = version;
 
               drv = devShells.default.overrideAttrs (oldAttrs: {
                 buildInputs =
                   (with pkgs; [
                     coreutils
-                    nix
+                    nix.out
                     curl.bin # Ensure the actual curl binary is included in the PATH
                     glibc.bin # Ensure the glibc binaries are included in the PATH
                     jq.bin