fix(license): remove cascading commercial-use bit encoding, clarify Allow Selling label (#941)

- _resolve_commercial_bits() no longer has Sell-implies-Image
  cascading; each CommercialUse value sets only its own bit,
  matching CivitAI's modern array-format API.
- Keep filter tag label as 'Allow Selling' for brevity; add
  title/tooltip 'Allow selling generated images' on hover.
- Same tooltip treatment for 'No Credit Required'.
- Add i18n keys for both tooltips across all 10 locales.

templates/components/header.html

@@ -218,10 +218,10 @@
   <div class="filter-section">
     <h4>{{ t('header.filter.license') }}</h4>
     <div class="filter-tags">
-      <div class="filter-tag license-tag" data-license="noCredit">
+      <div class="filter-tag license-tag" data-license="noCredit" title="{{ t('header.filter.noCreditRequiredTooltip') }}">
         {{ t('header.filter.noCreditRequired') }}
       </div>
-      <div class="filter-tag license-tag" data-license="allowSelling">
+      <div class="filter-tag license-tag" data-license="allowSelling" title="{{ t('header.filter.allowSellingGeneratedContentTooltip') }}">
         {{ t('header.filter.allowSellingGeneratedContent') }}
       </div>
     </div>