[pegit-h]

What does this PR do?

SceneBridge currently parses create patches and validateScene() against the built-in node union only. A node kind registered through the plugin registry can therefore work in core/plugin flows but still be rejected at the MCP bridge boundary.

This change keeps the built-in parser as the first path, then falls back to the registered schema for the node's type when the built-in parse fails. The same helper is used for create patches and scene validation.

A focused regression test registers a minimal plugin kind, creates it through applyPatch, and verifies that the resulting scene validates cleanly.

Built-in and unregistered node behavior is unchanged.

How to test

Validated against current main:

• bun x biome check packages/mcp/src/bridge/scene-bridge.ts packages/mcp/src/bridge/scene-bridge.test.ts
• bun test packages/mcp/src/bridge/scene-bridge.test.ts → 56 passed, 0 failed
• bunx turbo run test --filter=@pascal-app/mcp → 1,516 passed, 0 failed
• bun test packages/core/src/registry/plugin-v1-conformance.test.ts → 12 passed, 0 failed
• bun --cwd packages/mcp run build → passed
• bun run check → exit 0

Screenshots

Not applicable. This is a headless MCP bridge change.

Checklist

• I tested locally with bun dev (not applicable to this headless bridge change)
• My code follows the project's style (bun check)
• I updated relevant docs (no user-facing behavior or API documentation change)
• This PR targets the main branch

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Note

Low Risk
Localized parsing/validation change in the headless MCP bridge with regression tests; built-in node behavior is unchanged.

Overview
The MCP SceneBridge no longer validates nodes only against the built-in AnyNode union. It now uses a shared parseRegisteredNode helper that keeps parseNode as the first path and, on failure, validates against the plugin nodeRegistry schema for the node's type.

That helper is wired into applyPatch create validation and validateScene, so plugin kinds can be created through patches and pass scene checks when they match their registered schema; invalid plugin payloads still fail with schema errors.

A regression test registers a minimal plugin kind, creates it via applyPatch, and asserts valid/invalid value handling in both patch apply and validateScene.

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