feat(i18n): wrap 1103 hardcoded UI strings across Filament with __()

- Convert static $modelLabel/$pluralModelLabel/$title to getter methods
- Wrap ->label()/->placeholder()/->helperText()/->description()/->title()/->body() args
- Wrap Section::make()/Fieldset::make()/Notification::make()->title() args
- Fix RelationManagers::getTitle() signature to match parent (Model, string)
- Fix Pages::getTitle() to instance method (BasePage::getTitle is non-static)
- Extend lang/ru.json + lang/en.json with 700+ common terms; identity fallback for the rest
- Remove duplicate getters in 5 resources that had manual getModelLabel already

All 306 tests pass. Missing translations fall back to the RO key so the UI never breaks.

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

app/Filament/Tenant/Pages/ExcelImportWizard.php

@@ -27,7 +27,12 @@ class ExcelImportWizard extends Page
 
     protected static ?int $navigationSort = 65;
 
-    protected static ?string $title = 'Import factură Excel/CSV';
+    protected static ?string $title = null;
+
+    public function getTitle(): string
+    {
+        return __('Import factură Excel/CSV');
+    }
 
     protected string $view = 'filament.tenant.pages.excel-import-wizard';
 
@@ -62,11 +67,11 @@ class ExcelImportWizard extends Page
     public function goToStep2(): void
     {
         if (! $this->supplierId) {
-            Notification::make()->title('Selectează furnizorul')->danger()->send();
+            Notification::make()->title(__('Selectează furnizorul'))->danger()->send();
             return;
         }
         if (! $this->upload) {
-            Notification::make()->title('Încarcă fișierul Excel sau CSV')->danger()->send();
+            Notification::make()->title(__('Încarcă fișierul Excel sau CSV'))->danger()->send();
             return;
         }
 
@@ -96,7 +101,7 @@ class ExcelImportWizard extends Page
         $this->previewSummary = $result['summary'];
 
         if (empty($this->previewRows)) {
-            Notification::make()->title('Nu am găsit linii valide — verifică maparea coloanelor')->warning()->send();
+            Notification::make()->title(__('Nu am găsit linii valide — verifică maparea coloanelor'))->warning()->send();
             return;
         }