fix: update bundled DeepSeek Harness to rc.8

The desktop runtime still pinned the rc.6 Harness family. It now uses the coherent rc.8 package set, adapts the revised image-attachment limits and error contract, and derives release checks from the lockfile. The managed SSH Agent package remains unchanged.

Release note: 内置 DeepSeek Harness 已升级至 0.1.0-rc.8，并适配新版图片附件限制；托管 SSH Agent 包不受影响。

src/main/agent/deepseek-harness-control-protocol.ts

@@ -5,11 +5,13 @@ import {
   runtimeExtensionConfigurationSchema,
   runtimeExtensionIdSchema
 } from '../../shared/runtime-extension-contracts'
+import { bundledDeepSeekHarnessVersion } from './bundled-runtimes'
 
 export const DEEPSEEK_HARNESS_CONTROL_PROTOCOL =
   'goodbuddy.deepseek-harness.control'
 export const DEEPSEEK_HARNESS_CONTROL_VERSION = 2
-export const DEEPSEEK_HARNESS_HOST_VERSION = '0.1.0-rc.6'
+export const DEEPSEEK_HARNESS_HOST_VERSION =
+  bundledDeepSeekHarnessVersion
 export const DEEPSEEK_HARNESS_CREDENTIAL_REF =
   'GOODBUDDY_HARNESS_MODEL_API_KEY'
 export const DEEPSEEK_HARNESS_MAX_FRAME_BYTES =