refactor(core): Generalize binary data manager interface (no-changelog) (#7164)

Depends on: #7092 | Story:
[PAY-768](https://linear.app/n8n/issue/PAY-768)

This PR: 
- Generalizes the `IBinaryDataManager` interface.
- Adjusts `Filesystem.ts` to satisfy the interface.
- Sets up an S3 client stub to be filled in in the next PR.
- Turns `BinaryDataManager` into an injectable service.
- Adjusts the config schema and adds new validators.

Note that the PR looks large but all the main changes are in
`packages/core/src/binaryData`.

Out of scope:
- `BinaryDataManager` (now `BinaryDataService`) and `Filesystem.ts` (now
`fs.client.ts`) were slightly refactored for maintainability, but fully
overhauling them is **not** the focus of this PR, which is meant to
clear the way for the S3 implementation. Future improvements for these
two should include setting up a backwards-compatible dir structure that
makes it easier to locate binary data files to delete, removing
duplication, simplifying cloning methods, using integers for binary data
size instead of `prettyBytes()`, writing tests for existing binary data
logic, etc.

---------

Co-authored-by: कारतोफ्फेलस्क्रिप्ट™ <aditya@netroy.in>

packages/cli/src/Server.ts

@@ -26,7 +26,7 @@ import type { RequestOptions } from 'oauth-1.0a';
 import clientOAuth1 from 'oauth-1.0a';
 
 import {
-	BinaryDataManager,
+	BinaryDataService,
 	Credentials,
 	LoadMappingOptions,
 	LoadNodeParameterOptions,
@@ -202,6 +202,8 @@ export class Server extends AbstractServer {
 
 	push: Push;
 
+	binaryDataService: BinaryDataService;
+
 	constructor() {
 		super('main');
 
@@ -361,6 +363,7 @@ export class Server extends AbstractServer {
 		this.endpointPresetCredentials = config.getEnv('credentials.overwrite.endpoint');
 
 		this.push = Container.get(Push);
+		this.binaryDataService = Container.get(BinaryDataService);
 
 		await super.start();
 		LoggerProxy.debug(`Server ID: ${this.uniqueInstanceId}`);
@@ -1427,13 +1430,12 @@ export class Server extends AbstractServer {
 			async (req: BinaryDataRequest, res: express.Response): Promise<void> => {
 				// TODO UM: check if this needs permission check for UM
 				const identifier = req.params.path;
-				const binaryDataManager = BinaryDataManager.getInstance();
 				try {
-					const binaryPath = binaryDataManager.getBinaryPath(identifier);
+					const binaryPath = this.binaryDataService.getPath(identifier);
 					let { mode, fileName, mimeType } = req.query;
 					if (!fileName || !mimeType) {
 						try {
-							const metadata = await binaryDataManager.getBinaryMetadata(identifier);
+							const metadata = await this.binaryDataService.getMetadata(identifier);
 							fileName = metadata.fileName;
 							mimeType = metadata.mimeType;
 							res.setHeader('Content-Length', metadata.fileSize);