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/WidgetAdapterSpecs/New.hs

@@ -4,6 +4,7 @@ import Web.Types
 import Generated.Types
 import IHP.Prelude
 import IHP.ViewPrelude
+import Web.Routes ()
 
 data NewView = NewView
     { spec       :: !WidgetAdapterSpec
@@ -48,9 +49,7 @@ renderForm spec envelopes reportings = formFor spec [hsx|
             <label class="block text-sm font-medium text-gray-700 mb-1">Envelope Contract</label>
             <select name="envelopeContractId" class="w-full border border-gray-200 rounded px-3 py-2 text-sm">
                 <option value="">— None —</option>
-                {forEach envelopes (\e -> [hsx|
-                    <option value={tshow e.id}>v{e.contractVersion}</option>
-                |])}
+                {forEach envelopes renderEnvelopeOption}
             </select>
         </div>
 
@@ -58,9 +57,7 @@ renderForm spec envelopes reportings = formFor spec [hsx|
             <label class="block text-sm font-medium text-gray-700 mb-1">Reporting Contract</label>
             <select name="reportingContractId" class="w-full border border-gray-200 rounded px-3 py-2 text-sm">
                 <option value="">— None —</option>
-                {forEach reportings (\r -> [hsx|
-                    <option value={tshow r.id}>v{r.contractVersion}</option>
-                |])}
+                {forEach reportings renderReportingOption}
             </select>
         </div>
 
@@ -87,3 +84,9 @@ renderForm spec envelopes reportings = formFor spec [hsx|
         </div>
     </div>
 |]
+
+renderEnvelopeOption :: WidgetEnvelopeContract -> Html
+renderEnvelopeOption e = [hsx|<option value={tshow e.id}>v{e.contractVersion}</option>|]
+
+renderReportingOption :: WidgetReportingContract -> Html
+renderReportingOption r = [hsx|<option value={tshow r.id}>v{r.contractVersion}</option>|]