feat: implement file upload functionality and create file serving endpoint

src/routes/(admin)/admin/characters/+page.server.ts

@@ -3,6 +3,9 @@ import { character, devilFruit, arc, characterOverride } from '$lib/server/db/sc
 import { eq } from 'drizzle-orm';
 import { fail } from '@sveltejs/kit';
 import type { PageServerLoad, Actions } from './$types';
+import { writeFile } from 'fs/promises';
+import { join } from 'path';
+import { existsSync, mkdirSync } from 'fs';
 
 export const load: PageServerLoad = async () => {
 	const [charactersData, devilFruits, arcs, overrides] = await Promise.all([
@@ -101,8 +104,38 @@ export const actions: Actions = {
 
 			const updates: Record<string, any> = {};
 
+			// Handle file upload
+			const pictureFile = formData.get('pictureFile') as File;
+			const hasUploadedPicture = !!pictureFile && pictureFile.size > 0;
+			if (hasUploadedPicture) {
+				try {
+					const uploadsDir = join(process.cwd(), 'uploads');
+					if (!existsSync(uploadsDir)) {
+						mkdirSync(uploadsDir, { recursive: true });
+					}
+
+					// Get file extension
+					const extension = pictureFile.name.split('.').pop();
+					const filename = `${id}.${extension}`;
+					const filepath = join(uploadsDir, filename);
+
+					// Convert file to buffer and save
+					const buffer = Buffer.from(await pictureFile.arrayBuffer());
+					await writeFile(filepath, buffer);
+
+					// Update pictureUrl to point to the handler route
+					updates.pictureUrl = `/uploads/${filename}`;
+				} catch (error) {
+					console.error('File upload error:', error);
+					return fail(500, { error: 'Failed to upload file' });
+				}
+			}
+
 			formData.forEach((value, key) => {
-				if (key !== 'id') {
+				if (key !== 'id' && key !== 'pictureFile') {
+					if (hasUploadedPicture && key === 'pictureUrl') {
+						return;
+					}
 					// Handle integers (age, bounty, height, devilFruitId, arcId)
 					if (key === 'age' || key === 'bounty' || key === 'height' || key === 'devilFruitId' || key === 'arcId') {
 						const strValue = value as string;