feat(storage): add MinIO local storage and @manacore/shared-storage package

- Add MinIO service to docker-compose.dev.yml with auto-bucket initialization
- Create @manacore/shared-storage package with S3-compatible client
- Add factory functions for each project (Picture, Chat, ManaDeck, etc.)
- Include file utilities (generateFileKey, getContentType, validators)
- Update environment variables for S3/MinIO configuration
- Document storage architecture in CLAUDE.md

Local dev uses MinIO, production will use Hetzner Object Storage.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

packages/shared-storage/src/client.ts

@@ -0,0 +1,194 @@
+import {
+	S3Client,
+	PutObjectCommand,
+	GetObjectCommand,
+	DeleteObjectCommand,
+	ListObjectsV2Command,
+	HeadObjectCommand,
+	type PutObjectCommandInput,
+} from '@aws-sdk/client-s3';
+import { getSignedUrl } from '@aws-sdk/s3-request-presigner';
+import type {
+	StorageConfig,
+	BucketConfig,
+	UploadOptions,
+	PresignedUrlOptions,
+	UploadResult,
+	FileInfo,
+} from './types.js';
+
+/**
+ * S3-compatible storage client for MinIO (local) and Hetzner Object Storage (production)
+ */
+export class StorageClient {
+	private client: S3Client;
+	private bucket: BucketConfig;
+
+	constructor(config: StorageConfig, bucket: BucketConfig) {
+		this.client = new S3Client({
+			endpoint: config.endpoint,
+			region: config.region,
+			credentials: {
+				accessKeyId: config.accessKeyId,
+				secretAccessKey: config.secretAccessKey,
+			},
+			forcePathStyle: config.forcePathStyle ?? true,
+		});
+		this.bucket = bucket;
+	}
+
+	/**
+	 * Upload a file to the bucket
+	 */
+	async upload(
+		key: string,
+		body: Buffer | Uint8Array | string | ReadableStream,
+		options: UploadOptions = {}
+	): Promise<UploadResult> {
+		const input: PutObjectCommandInput = {
+			Bucket: this.bucket.name,
+			Key: key,
+			Body: body,
+			ContentType: options.contentType,
+			CacheControl: options.cacheControl,
+			Metadata: options.metadata,
+		};
+
+		if (options.public) {
+			input.ACL = 'public-read';
+		}
+
+		const command = new PutObjectCommand(input);
+		const result = await this.client.send(command);
+
+		return {
+			key,
+			url: this.getPublicUrl(key),
+			etag: result.ETag,
+		};
+	}
+
+	/**
+	 * Download a file from the bucket
+	 */
+	async download(key: string): Promise<Buffer> {
+		const command = new GetObjectCommand({
+			Bucket: this.bucket.name,
+			Key: key,
+		});
+
+		const response = await this.client.send(command);
+
+		if (!response.Body) {
+			throw new Error(`File not found: ${key}`);
+		}
+
+		// Convert stream to buffer
+		const chunks: Uint8Array[] = [];
+		const stream = response.Body as AsyncIterable<Uint8Array>;
+		for await (const chunk of stream) {
+			chunks.push(chunk);
+		}
+		return Buffer.concat(chunks);
+	}
+
+	/**
+	 * Delete a file from the bucket
+	 */
+	async delete(key: string): Promise<void> {
+		const command = new DeleteObjectCommand({
+			Bucket: this.bucket.name,
+			Key: key,
+		});
+
+		await this.client.send(command);
+	}
+
+	/**
+	 * Check if a file exists
+	 */
+	async exists(key: string): Promise<boolean> {
+		try {
+			const command = new HeadObjectCommand({
+				Bucket: this.bucket.name,
+				Key: key,
+			});
+			await this.client.send(command);
+			return true;
+		} catch {
+			return false;
+		}
+	}
+
+	/**
+	 * List files in the bucket with optional prefix
+	 */
+	async list(prefix?: string, maxKeys = 1000): Promise<FileInfo[]> {
+		const command = new ListObjectsV2Command({
+			Bucket: this.bucket.name,
+			Prefix: prefix,
+			MaxKeys: maxKeys,
+		});
+
+		const response = await this.client.send(command);
+
+		return (response.Contents ?? []).map((item) => ({
+			key: item.Key!,
+			size: item.Size ?? 0,
+			lastModified: item.LastModified ?? new Date(),
+			etag: item.ETag,
+		}));
+	}
+
+	/**
+	 * Generate a presigned URL for uploading (PUT)
+	 */
+	async getUploadUrl(key: string, options: PresignedUrlOptions = {}): Promise<string> {
+		const command = new PutObjectCommand({
+			Bucket: this.bucket.name,
+			Key: key,
+		});
+
+		return getSignedUrl(this.client, command, {
+			expiresIn: options.expiresIn ?? 3600,
+		});
+	}
+
+	/**
+	 * Generate a presigned URL for downloading (GET)
+	 */
+	async getDownloadUrl(key: string, options: PresignedUrlOptions = {}): Promise<string> {
+		const command = new GetObjectCommand({
+			Bucket: this.bucket.name,
+			Key: key,
+		});
+
+		return getSignedUrl(this.client, command, {
+			expiresIn: options.expiresIn ?? 3600,
+		});
+	}
+
+	/**
+	 * Get the public URL for a file (if bucket is public)
+	 */
+	getPublicUrl(key: string): string | undefined {
+		if (!this.bucket.publicUrl) {
+			return undefined;
+		}
+		return `${this.bucket.publicUrl}/${key}`;
+	}
+
+	/**
+	 * Get the underlying S3 client for advanced operations
+	 */
+	getS3Client(): S3Client {
+		return this.client;
+	}
+
+	/**
+	 * Get the bucket name
+	 */
+	getBucketName(): string {
+		return this.bucket.name;
+	}
+}