feat: sanction DM links and per-event colour coding (#13)

## Summary

- Adds resource links (appeal form, sanction logs, contact page, community invite) to all sanction DMs, separated from the sanction text by a Components v2 separator
- Adds a unique accent colour for every mod log and activity log event type, giving each action a distinct visual identity at a glance

## Changes

- `src/utils/components.ts` — Added `sanctionDmMessage` helper with two-section container (sanction text + links); added full `Colours` palette covering all sanction and activity event types; added `ColourKey` export
- `src/commands/{ban,kick,mute,softban,warn}.ts` — Updated DMs to use `sanctionDmMessage` with the appropriate colour
- `src/modules/logModAction.ts` / `logActivity.ts` — Thread `colour` parameter through to message builders
- All event and command files updated with their respective colours

✨ This PR was created with help from Hikari~ 🌸

Reviewed-on: #13
Co-authored-by: Hikari <hikari@nhcarrigan.com>
Co-committed-by: Hikari <hikari@nhcarrigan.com>

src/commands/mute.ts

@@ -14,7 +14,11 @@ import {
 } from "discord.js";
 import { logModerationAction } from "../modules/logModAction.js";
 import { sendSanction } from "../modules/sendSanction.js";
-import { errorReply, successReply } from "../utils/components.js";
+import {
+  errorReply,
+  sanctionDmMessage,
+  successReply,
+} from "../utils/components.js";
 import { logger } from "../utils/logger.js";
 import type { Command } from "../interfaces/command.js";
 
@@ -155,7 +159,10 @@ const muteCommand: Command = {
 
     try {
       await target.send(
-        `You have been muted in **${interaction.guild?.name ?? "the server"}** for **${durationLabel}**.\n**Reason:** ${reason}`,
+        sanctionDmMessage(
+          `You have been muted in **${interaction.guild?.name ?? "the server"}** for **${durationLabel}**.\n**Reason:** ${reason}`,
+          "mute",
+        ),
       );
     } catch {
       // DMs may be closed; continue without failing the command.
@@ -163,6 +170,7 @@ const muteCommand: Command = {
 
     await logModerationAction(interaction.client, {
       action:         "Member Muted",
+      colour:         "mute",
       emoji:          "🔇",
       moderatorTag:   interaction.user.username,
       reason:         reason,