fix: use 1m fallback for unknown model context

packages/client/src/i18n/locales/en.ts

@@ -1415,7 +1415,7 @@ export default {
     customType: 'Custom',
     provider: 'Provider',
     contextLength: 'Context Length',
-    contextLengthPlaceholder: 'e.g. 256000 (optional)',
+    contextLengthPlaceholder: 'Optional; estimated as 1000000 when unknown',
     apiMode: 'API Mode',
     local: 'Local ({host})',
     selectProviderRequired: 'Please select a provider',

packages/client/src/i18n/locales/zh.ts

@@ -1415,7 +1415,7 @@ export default {
     customType: '自定义',
     provider: 'Provider',
     contextLength: '上下文长度',
-    contextLengthPlaceholder: '例如 256000（可选）',
+    contextLengthPlaceholder: '可选；未知时按 1000000 估算',
     apiMode: 'API 模式',
     local: '本地 ({host})',
     selectProviderRequired: '请选择 Provider',

packages/server/src/services/hermes/model-context.ts

@@ -9,7 +9,7 @@ import { getCompatibleCustomProviders } from './custom-providers-compat'
 
 const HERMES_BASE = detectHermesHome()
 const MODELS_DEV_CACHE = resolve(HERMES_BASE, 'models_dev_cache.json')
-const DEFAULT_CONTEXT_LENGTH = 256_000
+const DEFAULT_CONTEXT_LENGTH = 1_000_000
 
 export interface ModelContextLengthOptions {
   profile?: string