feat: standardize command error handling (Sprint 4)

- Create withCommandErrorHandling utility in bot/lib/commandUtils.ts
- Migrate economy commands: daily, exam, pay, trivia
- Migrate inventory command: use
- Migrate admin/moderation commands: warn, case, cases, clearwarning,
  warnings, note, notes, create_color, listing, webhook, refresh,
  terminal, featureflags, settings, prune
- Add 9 unit tests for the utility
- Update AGENTS.md with new recommended error handling pattern

bot/commands/admin/terminal.ts

@@ -2,7 +2,8 @@
 import { createCommand } from "@shared/lib/utils";
 import { SlashCommandBuilder, PermissionFlagsBits, ChannelType, TextChannel } from "discord.js";
 import { terminalService } from "@shared/modules/terminal/terminal.service";
-import { createBaseEmbed, createErrorEmbed } from "@/lib/embeds";
+import { createErrorEmbed } from "@/lib/embeds";
+import { withCommandErrorHandling } from "@lib/commandUtils";
 
 export const terminal = createCommand({
     data: new SlashCommandBuilder()
@@ -23,15 +24,14 @@ export const terminal = createCommand({
                 return;
             }
 
-            await interaction.reply({ ephemeral: true, content: "Initializing terminal..." });
-
-            try {
-                await terminalService.init(channel as TextChannel);
-                await interaction.editReply({ content: "✅ Terminal initialized!" });
-            } catch (error) {
-                console.error(error);
-                await interaction.editReply({ content: "❌ Failed to initialize terminal." });
-            }
+            await withCommandErrorHandling(
+                interaction,
+                async () => {
+                    await terminalService.init(channel as TextChannel);
+                    await interaction.editReply({ content: "✅ Terminal initialized!" });
+                },
+                { ephemeral: true }
+            );
         }
     }
 });