v2.0.0 — Pure glue architecture: zero copied code, pluggable channels

BREAKING: Complete architectural rewrite.

Before: Copied x-reader's fetcher code into readers/ (1205 lines of borrowed code)
After: Pluggable channel system where each channel is a thin wrapper (~50 lines)
       around the best external tool for that platform. Zero copied code.

Architecture:
- channels/base.py — Universal Channel interface (read, search, check)
- channels/web.py — Jina Reader API (swappable)
- channels/github.py — GitHub API (swappable)
- channels/twitter.py — birdx + Jina fallback (swappable)
- channels/youtube.py — yt-dlp (swappable)
- channels/reddit.py — Reddit JSON API + proxy (swappable)
- channels/rss.py — feedparser (swappable)
- channels/bilibili.py — Bilibili API (swappable)
- channels/exa_search.py — Exa semantic search (swappable)

Key design: every backend can be swapped by changing ONE file.
YouTube dies? Change youtube.py. Exa sucks? Swap exa_search.py for Tavily.
Nothing else changes.

Removed: reader.py, schema.py, readers/, search/, utils/ (all x-reader code)
Tests: 36/36 passing

agent_eyes/channels/web.py

@@ -0,0 +1,49 @@
+# -*- coding: utf-8 -*-
+"""Web pages — via Jina Reader API (free, no config needed).
+
+Backend: Jina Reader (https://r.jina.ai)
+Swap to: Firecrawl, Trafilatura, or any other reader API
+"""
+
+import requests
+from .base import Channel, ReadResult
+
+
+class WebChannel(Channel):
+    name = "web"
+    description = "Web pages (any URL)"
+    backends = ["Jina Reader API"]
+    tier = 0
+
+    JINA_URL = "https://r.jina.ai/"
+
+    def can_handle(self, url: str) -> bool:
+        # Fallback — handles any URL not matched by other channels
+        return True
+
+    async def read(self, url: str, config=None) -> ReadResult:
+        resp = requests.get(
+            f"{self.JINA_URL}{url}",
+            headers={"Accept": "text/markdown"},
+            timeout=15,
+        )
+        resp.raise_for_status()
+        text = resp.text
+
+        # Extract title from first markdown heading
+        title = url
+        for line in text.split("\n"):
+            line = line.strip()
+            if line.startswith("# "):
+                title = line[2:].strip()
+                break
+            if line.startswith("Title:"):
+                title = line[6:].strip()
+                break
+
+        return ReadResult(
+            title=title,
+            content=text,
+            url=url,
+            platform="web",
+        )