feat(i18n): enhance locale support for rebate settings and report exports

- Updated English, Nepali, and Chinese locale files to include new translations for the "apply rebate to payout" feature, enhancing clarity on its functionality.
- Added new export options for previewing CSV and Excel files in reports, improving user experience with clearer export capabilities.
- Enhanced internationalization support across multiple locales to ensure consistent messaging in the admin interface.

src/i18n/locales/en/config.json

@@ -115,6 +115,7 @@
       "autoSettlement": "Run settlement automatically",
       "autoApprove": "Auto-approve settlement batches",
       "autoPayout": "Auto-credit winnings to wallets",
+      "applyRebateToPayout": "Deduct rebate again on winning payouts",
       "playRulesHtml": "Play rules HTML (i18n)",
       "playRulesHtmlDesc": "Rendered on the player play-rules page per locale. Leave empty to fall back to another language or the default empty state."
     },
@@ -123,7 +124,8 @@
       "cooldownMinutes": "How long to wait after publishing before entering settling. Use 0 to settle immediately.",
       "autoSettlement": "When disabled, tick will not run settlement automatically and admins must trigger it manually.",
       "autoApprove": "After cooldown ends and settlement completes, whether batches are automatically marked as approved.",
-      "autoPayout": "After a batch is approved, whether tick automatically credits winnings to player wallets."
+      "autoPayout": "After a batch is approved, whether tick automatically credits winnings to player wallets.",
+      "applyRebateToPayout": "When enabled, payout = gross win × (1 - rebate_rate_snapshot). Default off (rebate already reflected in actual deduct)."
     },
     "states": {
       "enabled": "Enabled",
@@ -333,9 +335,11 @@
       "d4": "4D rebate rate (%)"
     },
     "winEnjoy": {
-      "label": "Apply rebate on winning tickets",
-      "description": "Placeholder field. It can later be aligned with risk and settlement rules and persisted.",
-      "pendingNote": "Required by the product spec, but the API has no field yet. This row is informational only—you cannot change it here."
+      "label": "Deduct rebate on winning payouts",
+      "description": "Maps to settlement.apply_rebate_to_payout: when enabled, winning payout uses gross win × (1 - rebate_rate_snapshot).",
+      "hint": "Global switch; affects future settlement payouts immediately (not tied to odds version publish).",
+      "saveSuccess": "Winning-ticket rebate setting updated",
+      "saveFailed": "Update failed"
     },
     "effectiveTime": "Effective time (current active odds version)"
   },