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>

Web/View/Requirements/Index.hs

@@ -4,6 +4,7 @@ import Web.Types
 import Generated.Types
 import IHP.Prelude
 import IHP.ViewPrelude
+import Web.Routes ()
 
 data IndexView = IndexView
     { requirements :: ![Requirement]
@@ -15,11 +16,13 @@ instance View IndexView where
         <div class="flex items-center justify-between mb-6">
             <h1 class="text-2xl font-semibold">Requirements</h1>
         </div>
-        {if null requirements
-            then [hsx|<p class="text-sm text-gray-400">No requirements yet. Promote an accepted candidate to create one.</p>|]
-            else renderTable requirements candidates}
+        {renderRequirementsSection requirements candidates}
     |]
 
+renderRequirementsSection :: [Requirement] -> [RequirementCandidate] -> Html
+renderRequirementsSection [] _ = [hsx|<p class="text-sm text-gray-400">No requirements yet. Promote an accepted candidate to create one.</p>|]
+renderRequirementsSection reqs candidates = renderTable reqs candidates
+
 renderTable :: [Requirement] -> [RequirementCandidate] -> Html
 renderTable reqs candidates = [hsx|
     <div class="bg-white rounded-lg border border-gray-200 overflow-hidden">
@@ -43,7 +46,7 @@ renderRow :: [RequirementCandidate] -> Requirement -> Html
 renderRow candidates req = [hsx|
     <tr class="hover:bg-gray-50">
         <td class="px-4 py-3">
-            <a href={ShowRequirementAction { requirementId = req.id }}
+            <a href={ShowRequirementAction (req.id)}
                class="text-indigo-600 hover:text-indigo-800 font-medium">{req.title}</a>
         </td>
         <td class="px-4 py-3">