feat(web): switch to implementation-first capability wave

web/app/src/engine-client/WebEngineClient.ts

@@ -22,6 +22,7 @@ import type { RenderCapabilityRequest } from "../../../protocol/render-capabilit
 import type { CapabilityGateResult } from "../../../protocol/capability-gates";
 import { applyMeshGeometryDelta } from "../../../protocol/mesh-geometry-delta";
 import { createWorkerFault, type WorkerFault } from "../../../protocol/worker-fault";
+import { getWebEngineCommandCapability } from "../../../protocol/web-engine-capabilities";
 import type {
   PaintStrokeSessionBeginIR,
   PaintStrokeSessionCancelIR,
@@ -106,6 +107,9 @@ export class WebEngineClient {
   }
 
   async applyCommand(payload: WebEngineEditCommand): Promise<BlendOpenResult & { delta: SceneDelta; shaderCompile?: ShaderCompileReport }> {
+    if (!getWebEngineCommandCapability((payload as { type?: unknown }).type)) {
+      throw this.report("INVALID_ARGUMENT", `Unsupported WebEngine command: ${String((payload as { type?: unknown }).type)}`, true);
+    }
     const result = await this.request({ type: "applyCommand", payload });
     if (!result.snapshot || !result.delta) throw this.report("INVALID_ARGUMENT", "WebEngine 未返回命令结果", true);
     this.geometryBuffers = result.geometryDelta