fix(nix): add CI environment flags to prevent terminal rendering crash

Added CI=true, NO_COLOR=1, TERM=dumb, and NX_SKIP_NX_CACHE=true
to both mkViteApp.nix and landing.nix to prevent the vt100-rust
panic during Nix builds.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

nix/landing.nix

@@ -19,6 +19,10 @@ pkgs.buildNpmPackage {
     runHook preBuild
     export NX_DAEMON=false
     export HOME=$TMPDIR
+    export CI=true
+    export NO_COLOR=1
+    export TERM=dumb
+    export NX_SKIP_NX_CACHE=true
     npm run landing:build
     runHook postBuild
   '';

nix/mkViteApp.nix

@@ -20,6 +20,10 @@ pkgs.buildNpmPackage {
     runHook preBuild
     export NX_DAEMON=false
     export HOME=$TMPDIR
+    export CI=true
+    export NO_COLOR=1
+    export TERM=dumb
+    export NX_SKIP_NX_CACHE=true
     ${pkgs.lib.concatStringsSep "\n" (pkgs.lib.mapAttrsToList (k: v: "export ${k}=\"${v}\"") envVars)}
     npm run ${buildScript}
     runHook postBuild