feat(WP-0016/C1-C4): Layer 2 isolation and clean-base infrastructure

- Add Web/Controller/Prelude.hs (was missing; 8 controllers failed to import it)
- Add .ghci-core and scripts/compile-check-core to compile Layer 1+2 in
  isolation without loading Main.hs or any controller/view (Layer 3)
- Fix Application/Helper/BottleneckDetector.hs: replace coerce :: Id' -> UUID
  with unpackId (IHP Id' wraps a type family; Data.Coerce cannot cross it)
- Fix devenv.nix: add pkgs.nodePackages.tailwindcss so devenv process scripts
  find the tailwindcss binary (devenv v2 builds scripts with only local packages)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Web/Controller/Prelude.hs

@@ -0,0 +1,12 @@
+module Web.Controller.Prelude
+    ( module Web.Types
+    , module Generated.Types
+    , module IHP.Prelude
+    , module IHP.ControllerPrelude
+    ) where
+
+import Web.Types
+import Generated.Types
+import IHP.Prelude
+import IHP.ControllerPrelude
+import Web.Routes ()