fix(openclaw): sync Doubao context window to 262144

The OpenClaw DouBaoSeed preset hard-coded contextWindow 128000 while the
Codex preset/catalog uses 262144 for the same model, giving OpenClaw users
a too-small window that could compress or truncate long context early.
Align to 262144 and add a cross-preset consistency test asserting the
OpenClaw and Codex Doubao context windows stay equal, so neither side can
drift again.

src/config/openclawProviderPresets.ts

@@ -230,7 +230,7 @@ export const openclawProviderPresets: OpenClawProviderPreset[] = [
         {
           id: "doubao-seed-2-1-pro-260628",
           name: "DouBao Seed 2.1 Pro",
-          contextWindow: 128000,
+          contextWindow: 262144,
           cost: { input: 0.84, output: 4.2 },
         },
       ],