feat: Agent Reach 作为 Skill 安装

- 新增 agent-reach/SKILL.md — skills.sh 兼容格式
  安装: npx skills add Panniantong/Agent-Reach@agent-reach
- agent-reach install 自动检测 OpenClaw / Claude Code / 通用 Agent
  并在对应 skill 目录注册 SKILL.md
- SKILL.md 打包进 pip 包（agent_reach/skill/SKILL.md）
- README 中英文都加了 Skill 安装方式

agent_reach/skill/SKILL.md

@@ -0,0 +1,69 @@
+---
+name: agent-reach
+description: >
+  Give your AI agent eyes to see the entire internet. Read and search across
+  Twitter/X, Reddit, YouTube, GitHub, Bilibili, XiaoHongShu, RSS, and any web page
+  — all from a single CLI. Use when: (1) reading content from URLs (tweets, Reddit posts,
+  articles, videos), (2) searching across platforms (web, Twitter, Reddit, GitHub, YouTube,
+  Bilibili, XiaoHongShu), (3) checking channel health or updating Agent Reach.
+  Triggers: "search Twitter/Reddit/YouTube", "read this URL", "find posts about",
+  "搜索", "读取", "查一下", "看看这个链接".
+---
+
+# Agent Reach
+
+Read and search the internet across 9+ platforms via unified CLI.
+
+## Commands
+
+### Read any URL
+```bash
+agent-reach read <url>
+agent-reach read <url> --json    # structured output
+```
+Handles: tweets, Reddit posts, articles, YouTube (transcripts), GitHub repos, etc.
+
+### Search
+
+```bash
+agent-reach search "query"             # web search (Exa)
+agent-reach search-twitter "query"     # Twitter/X
+agent-reach search-reddit "query"      # Reddit (--sub <subreddit>)
+agent-reach search-github "query"      # GitHub (--lang <language>)
+agent-reach search-youtube "query"     # YouTube
+agent-reach search-bilibili "query"    # Bilibili (B站)
+agent-reach search-xhs "query"        # XiaoHongShu (小红书)
+```
+
+All search commands support `-n <count>` for number of results.
+
+### Management
+
+```bash
+agent-reach doctor        # channel status overview
+agent-reach watch         # quick health + update check (for scheduled tasks)
+agent-reach check-update  # check for new versions
+```
+
+### Configure channels
+
+```bash
+agent-reach configure twitter-cookies "auth_token=xxx; ct0=yyy"
+agent-reach configure proxy http://user:pass@ip:port
+agent-reach configure --from-browser chrome    # auto-extract cookies
+```
+
+## Channel Status Tiers
+
+- **Tier 0 (zero config):** Web, YouTube, RSS, Twitter (read-only via Jina)
+- **Tier 1 (free setup):** Exa web search (mcporter required)
+- **Tier 2 (user config):** Twitter search (cookie), Reddit full (proxy), GitHub (token), Bilibili (proxy), XiaoHongShu (MCP)
+
+Run `agent-reach doctor` to see which channels are active.
+
+## Tips
+
+- Always try `agent-reach read <url>` first for any URL — it auto-detects the platform
+- For Twitter cookies, recommend the user install [Cookie-Editor](https://chromewebstore.google.com/detail/cookie-editor/hlkenndednhfkekhgcdicdfddnkalmdm) Chrome extension
+- Reddit and Bilibili block server IPs — suggest a residential proxy (~$1/month) if on a server
+- If a channel breaks, run `agent-reach doctor` to diagnose