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/deepseek-harness-host.test.ts

@@ -34,7 +34,7 @@ describe('controlled DeepSeek Harness host', () => {
         api: 'openai-completions',
         provider: 'goodbuddy',
         model: 'deepseek-test',
-        harnessVersion: '0.1.0-rc.6',
+        harnessVersion: '0.1.0-rc.8',
         credentialRefs: ['GOODBUDDY_API_KEY'],
         dshHome: 'C:\\controlled-dsh-home',
         skillPackages: []
@@ -82,7 +82,7 @@ describe('controlled DeepSeek Harness host', () => {
       provider: 'goodbuddy',
       model: 'qwen-plus',
       supportsImageInput: true,
-      harnessVersion: '0.1.0-rc.6',
+      harnessVersion: '0.1.0-rc.8',
       credentialRefs: ['GOODBUDDY_API_KEY'],
       skillPackages: [],
       stream: {
@@ -140,7 +140,7 @@ describe('controlled DeepSeek Harness host', () => {
       api: 'openai-completions',
       provider: 'goodbuddy',
       model: 'deepseek-test',
-      harnessVersion: '0.1.0-rc.6',
+      harnessVersion: '0.1.0-rc.8',
       credentialRefs: ['GOODBUDDY_API_KEY'],
       skillPackages: [],
       stream: {
@@ -177,7 +177,7 @@ describe('controlled DeepSeek Harness host', () => {
       api: 'openai-completions',
       provider: 'goodbuddy',
       model: 'deepseek-test',
-      harnessVersion: '0.1.0-rc.6',
+      harnessVersion: '0.1.0-rc.8',
       credentialRefs: ['GOODBUDDY_API_KEY'],
       skillPackages: [],
       extensionPackages: [
@@ -232,7 +232,7 @@ describe('controlled DeepSeek Harness host', () => {
       api: 'openai-completions',
       provider: 'goodbuddy',
       model: 'deepseek-test',
-      harnessVersion: '0.1.0-rc.6',
+      harnessVersion: '0.1.0-rc.8',
       credentialRefs: ['GOODBUDDY_API_KEY'],
       skillPackages: [
         { id: 'web-3d-game', directory: skillDirectory }