fix: restore Telegram webhook-mode health after restarts

Landed from contributor PR #39313 by @fellanH.

Co-authored-by: Felix Hellström <30758862+fellanH@users.noreply.github.com>

src/config/types.telegram.ts

@@ -140,6 +140,8 @@ export type TelegramAccountConfig = {
   webhookHost?: string;
   /** Local webhook listener bind port (default: 8787). */
   webhookPort?: number;
+  /** Path to the self-signed certificate (PEM) to upload to Telegram during webhook registration. */
+  webhookCertPath?: string;
   /** Per-action tool gating (default: true for all). */
   actions?: TelegramActionConfig;
   /** Telegram thread/conversation binding overrides. */

src/config/zod-schema.providers-core.ts

@@ -221,6 +221,12 @@ export const TelegramAccountSchemaBase = z
       .describe(
         "Local bind port for the webhook listener. Defaults to 8787; set to 0 to let the OS assign an ephemeral port.",
       ),
+    webhookCertPath: z
+      .string()
+      .optional()
+      .describe(
+        "Path to the self-signed certificate (PEM) to upload to Telegram during webhook registration. Required for self-signed certs (direct IP or no domain).",
+      ),
     actions: z
       .object({
         reactions: z.boolean().optional(),