MCP: dashboard-get fails when tile has null insight (text tiles)

Bug

dashboard-get tool fails with a validation error when a dashboard contains a text tile (or any tile where insight is null).

Reproduction

1. Create a dashboard with a text tile (header/description)
2. Call dashboard-get with that dashboard ID via MCP

Error

Response validation failed on GET .../dashboards/1280858/:
[{
  "code": "invalid_type",
  "expected": "object",
  "received": "null",
  "path": ["tiles", 0, "insight"],
  "message": "Expected object, received null"
}]

Expected

The tool should handle tiles with null insight (text tiles, placeholder tiles) gracefully — either skip them or return them with insight: null.

Context

• MCP endpoint: https://mcp.posthog.com/mcp
• Tool: dashboard-get
• The API response itself is valid (response keys include tiles), but the MCP tool's Zod schema rejects it because it expects insight to always be an object.

Start at the dashboard-get MCP tool and the response Zod schema that validates dashboard tiles, then reproduce the failure with a text tile or another tile whose insight is null. Trace the tiles.insight validation and confirm the tool accepts null while continuing to validate ordinary insight objects.