fix(WP-0014): pre-flight compilation fixes, Tailwind pipeline, and admin seed

A2 — Compilation fixes:
- Remove inline FK constraints from Schema.sql; IHP schema compiler cannot
  parse them. Add 1744329600-restore-fk-constraints.sql migration to restore
  referential integrity at the DB level.
- Rename `#label` → `#label_` throughout to avoid clash with Haskell built-in.
- Fix `hub.id == hid` UUID comparisons to use `toUUID hub.id`.
- Replace non-existent `setStatus`/`respondJson` calls with
  `renderJsonWithStatusCode` throughout Api controllers.
- Fix qualified package import for `cryptohash-sha256` in Auth.hs.
- Add `CanSelect (Text, Text)` instance in Helper.View.
- Refactor HSX inline lambdas to named helper functions in 100+ views
  (GHC cannot infer types for anonymous functions inside quasi-quoted HSX).
- Fix missing imports (IHP.QueryBuilder, IHP.Fetch, Web.Routes, Only, etc.)
  across helpers and controllers.
- Remove duplicate `diffUTCTime` definition in BottleneckDetector.
- Change `createEventForHub` return type from `IO ResponseReceived` to `IO ()`.
- Seed type-registry vocabulary via 1744502400-seed-type-registries.sql
  (moved from Schema.sql where IHP does not execute INSERT statements).

A3 — Tailwind build pipeline:
- Add `tailwindcss` to flake.nix native packages.
- Uncomment `tailwind.exec` process in devenv shell config.
- Add tailwind/tailwind.config.js (scans Web/View/**/*.hs).
- Add tailwind/app.css with @tailwind directives.

A4 — Admin user seed:
- Add 1744416000-seed-admin-user.sql: inserts admin@inter-hub.local
  with bcrypt-hashed password admin1234! (cost 10).
- Add .env.example documenting all required environment variables
  and default admin credentials.

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

Application/Helper/View.hs

@@ -3,6 +3,15 @@ module Application.Helper.View where
 import IHP.ViewPrelude
 import Generated.Types
 import Web.Types
+import Web.Routes ()
+import IHP.View.Form.Select (CanSelect(..))
+
+-- | CanSelect instance for (Text, Text) tuples where fst is the label
+-- and snd is the value. Used by selectField when options are plain text pairs.
+instance CanSelect (Text, Text) where
+    type SelectValue (Text, Text) = Text
+    selectLabel = fst
+    selectValue = snd
 
 -- | Widget Envelope — wraps any widget's rendered content with IHF governance metadata.
 --
@@ -44,7 +53,7 @@ widgetEnvelope widget inner =
         {renderEnvelopeWarnings warnings}
         {inner}
         <div class="ihf-widget-controls mt-2">
-            <a href={WidgetAnnotationsAction { widgetId = widget.id }}
+            <a href={WidgetAnnotationsAction (widget.id)}
                class="ihf-annotate-btn text-xs text-gray-400 hover:text-indigo-600 border border-gray-200
                       rounded px-2 py-0.5 hover:border-indigo-300">
                 Annotate
@@ -70,10 +79,13 @@ renderEnvelopeWarnings [] = mempty
 renderEnvelopeWarnings ws = [hsx|
     <div class="bg-amber-50 border border-amber-200 rounded px-3 py-1 mb-1 text-xs text-amber-700">
         <strong>Envelope contract warning:</strong>
-        {forEach ws (\w -> [hsx|<div>{w}</div>|])}
+        {forEach ws renderWarningLine}
     </div>
 |]
 
+renderWarningLine :: Text -> Html
+renderWarningLine w = [hsx|<div>{w}</div>|]
+
 -- | Status badge colour for WidgetAdapterSpec and contract status values.
 adapterStatusBadge :: Text -> Text
 adapterStatusBadge "active"     = "bg-green-100 text-green-800"