Update MCP servers to use SSE endpoints (danny-avila#1388)

### TL;DR

Updated the vault-set-search MCP server to use SSE instead of stdio, and fixed the data_portal URL.

### What changed?

- Changed the vault-set-search MCP server configuration from stdio type to SSE type
- Replaced the npx command with a direct URL to the SSE endpoint: `https://proxy.shopify.ai/mcp/vault_set/sse`
- Added Authorization header with OpenAI API key for the vault-set-search server
- Updated the data_portal URL from `https://proxy.shopify.ai/mcp/data_portal` to `https://proxy.shopify.ai/mcp/data_portal/sse`

### Why make this change?

Switching vault-set-search from stdio to SSE provides a more efficient and standardized communication method. This change aligns with our architecture patterns and ensures consistent implementation across MCP servers. The data_portal URL update ensures proper endpoint addressing.

Author: samuelpath

librechat.yaml

@@ -121,10 +121,11 @@ interface:
 
 mcpServers:
   vault-set-search:
-    type: 'stdio'
-    command: 'npx'
-    args: ['--registry=https://npm.shopify.io/node/', '-y', 'vault-set-mcp-ts']
+    type: 'sse'
+    url: https://proxy.shopify.ai/mcp/vault_set/sse
     iconPath: '/assets/vaultbot-logo.svg'
+    headers:
+      Authorization: 'Bearer ${OPENAI_API_KEY}'
 
   scout:
     type: 'stdio'
@@ -157,7 +158,7 @@ mcpServers:
 
   data_portal:
     type: 'sse'
-    url: https://proxy.shopify.ai/mcp/data_portal
+    url: https://proxy.shopify.ai/mcp/data_portal/sse
     iconPath: '/assets/data_portal.png'
     headers:
       Authorization: 'Bearer ${OPENAI_API_KEY}'