feat(version): extension reports its version; doctor shows all-component coherence

The upgrade story spanned four parts (CLI, daemon, extension, skill) with no
single view and — worst — the extension was a total black box: nothing reported
which build was live, so a user could sit on a stale extension with zero signal.

- ext (0.4.7): on connect the extension sends a `hello` with
  chrome.runtime.getManifest().version; the native-messaging host records it to a
  `relay-ext-version` sidecar (next to relay-cdp-url, removed on exit).
- build.rs embeds the shipped extension version (AB_CONNECT_VERSION, read from the
  ext manifest at compile time) so the CLI knows what extension it expects.
- `chrome-use doctor` gains a Versions section: CLI (vs the cached latest from the
  background update check), extension (connected version vs the bundled expected —
  warns + tells you to reload it in Chrome if behind), and skill (bundled, version-
  locked; `skills add` copies may be stale). Daemon coherence was already covered.

So 'which of the four parts is on what version, and what needs upgrading' is now
one command. Verified: doctor warns on a simulated old extension and passes on a
current one; gracefully shows 'not connected / predates reporting' when the host
hasn't learned a version yet.

cli/build.rs

@@ -3,6 +3,23 @@ use std::env;
 use std::fs;
 use std::path::Path;
 
+/// Embed the version of the `ab-connect` extension this CLI ships alongside, so
+/// `doctor` can tell a connected extension "you're older than what this CLI
+/// expects, update it." Read from the extension manifest at build time so it
+/// stays in sync with whatever extension version is in the same checkout/release
+/// (the ext is on its own 0.4.x line, separate from the CLI version). Falls back
+/// to "unknown" if the manifest can't be read.
+fn embed_extension_version() {
+    let manifest = Path::new("../extensions/ab-connect/manifest.json");
+    println!("cargo:rerun-if-changed=../extensions/ab-connect/manifest.json");
+    let version = fs::read_to_string(manifest)
+        .ok()
+        .and_then(|s| serde_json::from_str::<serde_json::Value>(&s).ok())
+        .and_then(|v| v.get("version").and_then(|x| x.as_str()).map(String::from))
+        .unwrap_or_else(|| "unknown".to_string());
+    println!("cargo:rustc-env=AB_CONNECT_VERSION={}", version);
+}
+
 /// Ensure `packages/dashboard/out/` exists so `rust-embed` doesn't fail during
 /// Rust-only dev builds where the dashboard hasn't been built. The placeholder
 /// `index.html` is only written when the directory is completely absent.
@@ -20,6 +37,7 @@ fn ensure_dashboard_dir() {
 
 fn main() {
     ensure_dashboard_dir();
+    embed_extension_version();
 
     let protocol_dir = Path::new("cdp-protocol");
     let out_dir = env::var("OUT_DIR").unwrap();

cli/src/connect.rs

@@ -449,6 +449,28 @@ pub fn relay_url() -> Option<String> {
     }
 }
 
+/// Sidecar recording the connected extension's version, written by the host when
+/// it receives the extension's `hello` (sibling of `relay-cdp-url`). Lets
+/// `doctor` surface which extension build is live without a CDP round-trip.
+fn relay_ext_version_path() -> PathBuf {
+    relay_url_path().with_file_name("relay-ext-version")
+}
+
+/// Version of the connected `ab-connect` extension, if the host learned it from
+/// the extension's `hello`. `None` when no extension has connected since the
+/// host started, or the extension predates version reporting.
+pub fn relay_ext_version() -> Option<String> {
+    let s = std::fs::read_to_string(relay_ext_version_path())
+        .ok()?
+        .trim()
+        .to_string();
+    if s.is_empty() {
+        None
+    } else {
+        Some(s)
+    }
+}
+
 /// Hidden `__nm-host` mode: launched by Chrome for the ab-connect extension.
 ///
 /// Bridges the extension (native-messaging stdio, envelope protocol) to a local
@@ -570,6 +592,15 @@ async fn nm_host_main() {
             Ok(v) => v,
             Err(_) => continue,
         };
+        // Extension version handshake: record it next to the relay URL so
+        // `doctor` can report which extension build is live (and whether it's
+        // behind). Best-effort; the message carries no CDP payload.
+        if v.get("method").and_then(|m| m.as_str()) == Some("hello") {
+            if let Some(ver) = v.get("version").and_then(|x| x.as_str()) {
+                let _ = std::fs::write(relay_ext_version_path(), ver);
+            }
+            continue;
+        }
         let outs = {
             let mut s = state.lock().await;
             s.handle_ext_message(&v, "")
@@ -602,6 +633,7 @@ async fn nm_host_main() {
     }
     nm_log("[nm-host] stdin EOF — Chrome closed the port");
     let _ = std::fs::remove_file(relay_url_path());
+    let _ = std::fs::remove_file(relay_ext_version_path());
 }
 
 #[allow(clippy::too_many_arguments)]

cli/src/doctor/mod.rs

@@ -18,6 +18,7 @@ mod launch;
 mod network;
 mod providers;
 mod security;
+mod versions;
 
 use serde_json::{json, Value};
 
@@ -97,6 +98,7 @@ pub fn run_doctor(opts: DoctorOptions) -> i32 {
     let mut fixed: Vec<String> = Vec::new();
 
     environment::check(&mut checks);
+    versions::check(&mut checks);
     chrome::check(&mut checks);
     daemon::check(&mut checks);
     config::check(&mut checks);

cli/src/doctor/versions.rs

@@ -0,0 +1,89 @@
+//! Version-coherence checks across all four moving parts: the CLI binary, the
+//! per-session daemons (covered by `daemon.rs`), the connected `ab-connect`
+//! extension, and the bundled skill. The extension was previously a black box —
+//! nothing reported which build was live — so a user could sit on an old
+//! extension with no signal. The extension now reports its version over the
+//! relay (`hello`), the host records it, and this surfaces it in one place.
+
+use super::{Check, Status};
+use crate::{connect, upgrade};
+
+pub(super) fn check(checks: &mut Vec<Check>) {
+    let category = "Versions";
+    let cli_version = env!("CARGO_PKG_VERSION");
+
+    // CLI — compare against the latest seen by the background update check.
+    match upgrade::cached_latest_version() {
+        Some(latest) if upgrade::version_is_newer(&latest, cli_version) => {
+            checks.push(
+                Check::new(
+                    "versions.cli",
+                    category,
+                    Status::Warn,
+                    format!("CLI {cli_version} (newer available: {latest})"),
+                )
+                .with_fix("chrome-use upgrade".to_string()),
+            );
+        }
+        _ => {
+            checks.push(Check::new(
+                "versions.cli",
+                category,
+                Status::Pass,
+                format!("CLI {cli_version}"),
+            ));
+        }
+    }
+
+    // Extension — the build this CLI shipped alongside (embedded at compile time
+    // from the extension manifest) is what we expect to be running.
+    let expected_ext = env!("AB_CONNECT_VERSION");
+    match connect::relay_ext_version() {
+        Some(ext) if upgrade::version_is_newer(expected_ext, &ext) => {
+            checks.push(
+                Check::new(
+                    "versions.extension",
+                    category,
+                    Status::Warn,
+                    format!("extension {ext} is behind the bundled {expected_ext}"),
+                )
+                .with_fix(
+                    "update ab-connect in Chrome: chrome://extensions \u{2192} reload \
+                     (or wait for the Web Store auto-update)"
+                        .to_string(),
+                ),
+            );
+        }
+        Some(ext) => {
+            checks.push(Check::new(
+                "versions.extension",
+                category,
+                Status::Pass,
+                format!("extension {ext}"),
+            ));
+        }
+        None => {
+            checks.push(Check::new(
+                "versions.extension",
+                category,
+                Status::Info,
+                format!(
+                    "extension not connected (or it predates version reporting — \
+                     expected {expected_ext})"
+                ),
+            ));
+        }
+    }
+
+    // Skill — ships inside the same release artifact as the binary, so it's
+    // version-locked here. Copies made elsewhere via `skills add` aren't.
+    checks.push(Check::new(
+        "versions.skill",
+        category,
+        Status::Info,
+        format!(
+            "skills bundled with this CLI ({cli_version}); copies made via `skills add` \
+             elsewhere may be stale — re-run to refresh"
+        ),
+    ));
+}

cli/src/upgrade.rs

@@ -52,6 +52,27 @@ fn is_newer(latest: &str, current: &str) -> bool {
     matches!((parse_version(latest), parse_version(current)), (Some(l), Some(c)) if l > c)
 }
 
+/// Public semver-ish comparison (`latest` strictly newer than `current`), so
+/// `doctor` can flag a stale extension/CLI without re-implementing parsing.
+pub fn version_is_newer(latest: &str, current: &str) -> bool {
+    is_newer(latest, current)
+}
+
+/// The latest CLI version recorded by the background update check, if any.
+/// `doctor` uses it to show "a newer chrome-use is available" without a network
+/// call (the `__update-check` worker refreshes the cache out of band).
+pub fn cached_latest_version() -> Option<String> {
+    std::fs::read_to_string(update_cache_path())
+        .ok()
+        .and_then(|s| serde_json::from_str::<serde_json::Value>(&s).ok())
+        .and_then(|j| {
+            j.get("latest")
+                .and_then(|v| v.as_str())
+                .map(|s| s.to_string())
+        })
+        .filter(|s| !s.is_empty())
+}
+
 /// Hidden `__update-check` subcommand: fetch the latest release tag and cache it.
 /// Spawned detached by [`maybe_notify_update`] so the network call never blocks a
 /// real command. Uses `curl` (no extra deps, matches `upgrade`).

extensions/ab-connect/background.js

@@ -108,6 +108,12 @@ function connectHost() {
     // reconnect. Keep chrome.debugger attached so reconnect is cheap.
     for (const tabId of tabs.keys()) setBadge(tabId, 'connecting')
   })
+  // Report our version so the host can tell the CLI/`doctor` which extension
+  // build is live (otherwise the extension version is a black box — the user
+  // can't tell they're on an old one). Best-effort; ignored by older hosts.
+  try {
+    postToHost({ method: 'hello', version: chrome.runtime.getManifest().version })
+  } catch {}
   // Tell the daemon about everything we already have attached, then attach
   // anything new.
   reannounceAttachedTabs()

extensions/ab-connect/manifest.json

@@ -1,7 +1,7 @@
 {
   "manifest_version": 3,
   "name": "chrome-use",
-  "version": "0.4.6",
+  "version": "0.4.7",
   "description": "Let chrome-use drive your logged-in Chrome \u2014 install once, no token, no per-use confirmation.",
   "key": "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA6vQIyscGIPYPZdSpPwPL0+0gxUROyRgCpmvCSDoc8XUm4qm97VbKnD9Ijc1lV22lNWZtE78gaRjt6BeSfuMgnBymnhLKjN1gU6AI5QUU0mrJyeHdWKvrKQR5FmsM2A7Xr1ykE2SiiS8zNUS3Y/6O5l+Nva7wrVy6E4a2dkBVQkOsu+DV+nEZvhIyuDY5D5SPXqNwUTWTaglwj5mjvHz36xSwCWlPmrtJ+ED0AUyrb2z4GIOmvk4kqtBVrh/UD058klLo4CkYOnIybB5aV6WYuwarfPY4bF/dLggPem+ewLNTUNBuwrxj/A4nUv0LJTuRO8rR7f8WR9qnRCY0Ic5saQIDAQAB",
   "icons": {