feat(handlers): Add in-memory HTTP-01 challenge handler and rename file-based handler to Http01Webroot

ts/handlers/Http01MemoryHandler.ts

@@ -0,0 +1,67 @@
+import type { IChallengeHandler } from './IChallengeHandler.js';
+
+/**
+ * HTTP-01 ACME challenge handler using in-memory storage.
+ * Stores challenge tokens and key authorizations in memory
+ * and serves them via handleRequest for arbitrary HTTP servers.
+ */
+export interface Http01MemoryHandlerChallenge {
+  type: string;
+  token: string;
+  keyAuthorization: string;
+  webPath: string;
+}
+
+export class Http01MemoryHandler implements IChallengeHandler<Http01MemoryHandlerChallenge> {
+  private store: Map<string, string> = new Map();
+
+  public getSupportedTypes(): string[] {
+    return ['http-01'];
+  }
+
+  public async prepare(ch: Http01MemoryHandlerChallenge): Promise<void> {
+    this.store.set(ch.token, ch.keyAuthorization);
+  }
+
+  public async verify(_ch: Http01MemoryHandlerChallenge): Promise<void> {
+    // No-op
+    return;
+  }
+
+  public async cleanup(ch: Http01MemoryHandlerChallenge): Promise<void> {
+    this.store.delete(ch.token);
+  }
+
+  /**
+   * HTTP request handler for serving ACME HTTP-01 challenges.
+   * @param req HTTP request object (should have url property)
+   * @param res HTTP response object
+   * @param next Optional next() callback for Express-style fallthrough
+   */
+  public handleRequest(req: any, res: any, next?: () => void): void {
+    const url = req.url || '';
+    const prefix = '/.well-known/acme-challenge/';
+    if (!url.startsWith(prefix)) {
+      if (next) {
+        return next();
+      }
+      res.statusCode = 404;
+      return res.end();
+    }
+    const token = url.slice(prefix.length);
+    const keyAuth = this.store.get(token);
+    if (keyAuth !== undefined) {
+      if (typeof res.status === 'function' && typeof res.send === 'function') {
+        return res.status(200).send(keyAuth);
+      }
+      res.statusCode = 200;
+      res.setHeader('content-type', 'text/plain');
+      return res.end(keyAuth);
+    }
+    if (next) {
+      return next();
+    }
+    res.statusCode = 404;
+    return res.end();
+  }
+}