rebrand: agent-browser-stealth → chrome-use, de-fork, reset to v1.0.0

Standalone product rename across the whole repo (issue: project identity):

- Binary/package/repo/skill/docs: agent-browser[-stealth] → chrome-use
  (single binary name `chrome-use`; old aliases agent-browser/abs dropped).
- Version: 0.27.0-fork.51 → 1.0.0 (drop the upstream-fork counter).
- Native-messaging host: com.agent_browser.connect → com.leeguoo.chrome_use
  (CLI + ab-connect extension in lockstep — this is a breaking handshake change,
  extension bumped 0.4.2 → 0.5.0, needs a Web Store republish).
- Config dir: ~/.agent-browser → ~/.chrome-use.
- README/zh: reframed from "stealth fork of agent-browser" to a standalone
  product with a small `originally based on vercel-labs/agent-browser` credit.
- Kept AGENT_BROWSER_* env vars working (63 vars across the codebase; renaming
  them would break every existing script/skill for no user-facing gain).

Build green, 802 unit tests pass, fmt + clippy clean. Upstream attribution to
vercel-labs/agent-browser preserved.

cli/src/flags.rs

@@ -4,9 +4,9 @@ use std::env;
 use std::fs;
 use std::path::{Path, PathBuf};
 
-const CONFIG_DIR: &str = ".agent-browser";
+const CONFIG_DIR: &str = ".chrome-use";
 const CONFIG_FILENAME: &str = "config.json";
-const PROJECT_CONFIG_FILENAME: &str = "agent-browser.json";
+const PROJECT_CONFIG_FILENAME: &str = "chrome-use.json";
 
 /// Parse idle timeout from user-friendly format.
 /// Supports: "10s" (seconds), "3m" (minutes), "1h" (hours), or raw milliseconds.
@@ -1344,7 +1344,7 @@ mod tests {
 
     #[test]
     fn test_load_config_missing_file_returns_none() {
-        let result = read_config_file(&PathBuf::from("/nonexistent/agent-browser.json"));
+        let result = read_config_file(&PathBuf::from("/nonexistent/chrome-use.json"));
         assert!(result.is_none());
     }