Support deep linking MCP (#1550)

<!-- CURSOR_SUMMARY -->
> [!NOTE]
> Adds support for `dyad://add-mcp-server` deep links that prefill MCP
server settings, and updates deep link context/consumers to use
timestamp-based effects and clearing to avoid repeat handling.
> 
> - **Deep Link Infrastructure**:
> - Introduce `src/ipc/deep_link_data.ts` with zod schema
(`AddMcpServerConfigSchema`) and typed `DeepLinkData`.
> - Extend `DeepLinkContext` with `clearLastDeepLink`, timestamped
events, and auto-navigate to `/settings#tools-mcp` on `add-mcp-server`.
> - **Main Process**:
>   - Handle `dyad://add-mcp-server?name=...&config=...`:
> - Base64-decode and validate `config`; send `deep-link-received` with
typed payload or show error.
> - **Settings UI (MCP)**:
> - In `ToolsMcpSettings`, prefill form from `add-mcp-server` payload
(supports `stdio` command/args and `http` url) and show info toast;
clear deep link after handling.
> - **Connectors/UI**:
>   - Update `TitleBar`, `NeonConnector`, `SupabaseConnector` to:
> - Depend on `lastDeepLink?.timestamp` and call `clearLastDeepLink()`
after handling (`dyad-pro-return`, `neon-oauth-return`,
`supabase-oauth-return`).
> - **IPC Renderer**:
>   - Use centralized `DeepLinkData` types in `ipc_client.ts`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
294a9c6f38442241b54e9bcbe19a7a772d338ee0. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

src/ipc/ipc_client.ts

@@ -77,6 +77,7 @@ import type {
   ProposalResult,
 } from "@/lib/schemas";
 import { showError } from "@/lib/toast";
+import { DeepLinkData } from "./deep_link_data";
 
 export interface ChatStreamCallbacks {
   onUpdate: (messages: Message[]) => void;
@@ -102,10 +103,6 @@ export interface GitHubDeviceFlowErrorData {
   error: string;
 }
 
-export interface DeepLinkData {
-  type: string;
-}
-
 interface DeleteCustomModelParams {
   providerId: string;
   modelApiName: string;