feat(hints): contextual help system + FAQ page (MVP)

Infrastructure for a portal-wide in-app help system:

* Users have hints_enabled (default true) and dismissed_hints (JSON
  array) columns. User::shouldSeeHint(key) checks both.
* app/Support/Hints.php — single-source-of-truth registry with 14
  pilot hints across Service (5), CRM (3), Depozit (3), Finanțe (3).
  Each entry has RO/RU/EN title + body + optional next-step + links.
* <x-hint key="wo.dashboard.overview" /> Blade component renders a
  small "?" icon with Alpine.js popover; the popover shows title,
  body, next-step, related links and an "X" button that POSTs to
  /app/hints/{key}/dismiss.
* HintController handles dismiss (per key), toggle (global on/off)
  and reset (clear dismissed + re-enable). Routes are auth:web.
* /app/faq page (Filament Page under Admin group) renders the whole
  registry grouped by area with a live search box and buttons to
  toggle global hints or reset dismissed ones.
* Wired 3 pilot hints into the WO dashboard: title (overview), Docs
  tab PDF preview, and the Chat client card.

Follow-ups: extend registry to cover more pages and add <x-hint>
tags where useful. Filament resource fields can also reuse the same
copy via ->hint()/->helperText().

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

lang/en/nav.php

@@ -17,6 +17,7 @@ return [
     ],
 
     'label' => [
+        'FAQ & Ghid' => 'FAQ & Guide',
         'API Tokens' => 'API Tokens',
         'Achiziții' => 'Purchases',
         'Angajați' => 'Employees',