Refactor leveling form to use Discord multiplier editor and enhance localization

- Replaced text area inputs for role and channel multipliers with DiscordMultiplierEditor components for improved user experience.
- Updated state management to handle multiplier entries as objects instead of text, enhancing data integrity.
- Enhanced localization messages for multipliers, including error handling and hints for user guidance.

apps/webui/src/messages/en.json

@@ -318,13 +318,22 @@
       "noXpRoles": "No-XP roles",
       "roleMultipliers": "Role multipliers",
       "channelMultipliers": "Channel multipliers",
-      "multiplierHint": "One entry per line in the format id:multiplier, e.g. 123456789012345678:1.5",
+      "multiplierHint": "Pick a role or channel and set a multiplier (e.g. 1.5).",
+      "multiplierValue": "Multiplier",
+      "addMultiplier": "Add multiplier",
+      "errors": {
+        "multiplierMissingId": "Every multiplier needs a role or channel.",
+        "multiplierInvalid": "Multipliers must be a positive number.",
+        "multiplierDuplicate": "Each role or channel may only appear once."
+      },
       "levelUpTitle": "Level-up message",
       "levelUpMode": "Mode",
-      "mode.CHANNEL": "Channel",
-      "mode.DM": "Direct message",
-      "mode.OFF": "Off",
-      "levelUpChannelId": "Level-up channel ID",
+      "modes": {
+        "CHANNEL": "Channel",
+        "DM": "Direct message",
+        "OFF": "Off"
+      },
+      "levelUpChannelId": "Level-up channel",
       "levelUpMessage": "Message content",
       "stackRewards": "Stack role rewards",
       "rankCardTitle": "Rank card",
@@ -358,10 +367,12 @@
       "description": "Configure how support tickets are created and managed.",
       "enabledLabel": "Tickets module enabled",
       "mode": "Ticket mode",
-      "mode.CHANNEL": "Private channel",
-      "mode.THREAD": "Private thread",
+      "modes": {
+        "CHANNEL": "Private channel",
+        "THREAD": "Private thread"
+      },
       "categoryId": "Ticket category ID",
-      "logChannelId": "Log channel ID",
+      "logChannelId": "Log channel",
       "inactivityHours": "Auto-close after inactivity (hours)",
       "transcriptDm": "DM transcript to ticket creator",
       "transcriptDmHint": "Sends a transcript to the user via DM once their ticket is closed.",