feat: skill 随插件自动注册，免去 extra_skill_dirs 配置

kimi.plugin.json 声明 skills:["./skills"]，/plugins install 后 /skill kimi-eyes 经 PluginSkillSource 自动注册（源码 manifest.ts:100 + pluginSkillRoots 全链路证实）；package.json files 补 skills/；README（中英）与网页把「两步配置」简化为「一步」（只声明 image_in）。1.0.7 → 1.0.8。

package.json

@@ -1,6 +1,6 @@
 {
   "name": "kimi-eyes",
-  "version": "1.0.7",
+  "version": "1.0.8",
   "description": "Give non-multimodal models in Kimi Code the ability to analyze images and screenshots via a user-configured VLM (OpenAI-compatible or Anthropic protocol).",
   "keywords": [
     "kimi",
@@ -24,6 +24,7 @@
   "files": [
     "mcp/",
     "scripts/",
+    "skills/",
     "SYSTEM.md",
     "kimi.plugin.json",
     "setup.mjs",