channels: find_daemon path walking, consistent pane_id, auto-start

find_daemon() replaces daemon_sock() — walks the dot-delimited channel
path from most-specific to least looking for a daemon socket, and
auto-starts via the supervisor if none is found. All channel tools
(recv, send, open, close) use the same resolution path.

Fix tmux daemon to use pane_id consistently for both pipe-pane and
send-keys (send-keys -t <label> doesn't work, needs the %N pane id).
Store label→pane_id mapping in State instead of bare label vec.

Gracefully handle missing tmux.json5 — start with empty pane list
since panes are added dynamically via the open RPC.

Co-Authored-By: Proof of Concept <poc@bcachefs.org>

src/agent/tools/channels.rs

@@ -67,7 +67,7 @@ fn default_min_count() -> u32 { 20 }
 async fn channel_recv(args: &serde_json::Value) -> Result<String> {
     let a: RecvArgs = serde_json::from_value(args.clone())
         .context("invalid channel_recv arguments")?;
-    let sock = daemon_sock(&a.channel)?;
+    let (sock, _) = find_daemon(&a.channel)?;
     let channel = a.channel;
     let all_new = a.all_new;
     let min_count = a.min_count;
@@ -90,7 +90,7 @@ struct SendArgs {
 async fn channel_send(args: &serde_json::Value) -> Result<String> {
     let a: SendArgs = serde_json::from_value(args.clone())
         .context("invalid channel_send arguments")?;
-    let sock = daemon_sock(&a.channel)?;
+    let (sock, _) = find_daemon(&a.channel)?;
     let channel = a.channel;
     let message = a.message;
     tokio::task::spawn_blocking(move || {
@@ -119,13 +119,12 @@ async fn channel_open(args: &serde_json::Value) -> Result<String> {
     let label = args.get("label").and_then(|v| v.as_str())
         .context("label is required")?
         .to_string();
-    let prefix = label.split('.').next().unwrap_or("tmux");
-    let sock = daemon_sock(prefix)?;
+    let (sock, sublabel) = find_daemon(&label)?;
     tokio::task::spawn_blocking(move || {
         let rt = tokio::runtime::Builder::new_current_thread()
             .enable_all().build().unwrap();
         let local = tokio::task::LocalSet::new();
-        local.block_on(&rt, rpc_open(&sock, &label))
+        local.block_on(&rt, rpc_open(&sock, &sublabel))
     }).await?
         .map_err(|e| anyhow::anyhow!("{}", e))
 }
@@ -134,7 +133,7 @@ async fn channel_close(args: &serde_json::Value) -> Result<String> {
     let channel = args.get("channel").and_then(|v| v.as_str())
         .context("channel is required")?
         .to_string();
-    let sock = daemon_sock(&channel)?;
+    let (sock, _) = find_daemon(&channel)?;
     tokio::task::spawn_blocking(move || {
         let rt = tokio::runtime::Builder::new_current_thread()
             .enable_all().build().unwrap();
@@ -144,7 +143,7 @@ async fn channel_close(args: &serde_json::Value) -> Result<String> {
         .map_err(|e| anyhow::anyhow!("{}", e))
 }
 
-// ── Socket helpers ─────────────────────────────────────────────
+// ── Daemon resolution ─────────────────────────────────────────
 
 fn channels_dir() -> std::path::PathBuf {
     dirs::home_dir()
@@ -152,13 +151,64 @@ fn channels_dir() -> std::path::PathBuf {
         .join(".consciousness/channels")
 }
 
-fn daemon_sock(channel: &str) -> Result<std::path::PathBuf> {
-    let prefix = channel.split('.').next().unwrap_or("");
-    let sock = channels_dir().join(format!("{}.sock", prefix));
-    if !sock.exists() {
-        anyhow::bail!("no daemon for channel: {}", channel);
+/// Resolve a channel path to a daemon socket.
+///
+/// Walks the dot-delimited path from most-specific to least,
+/// looking for a daemon socket at each level:
+///   "tmux.ktest"           → finds tmux.sock, returns ("tmux.sock", "ktest")
+///   "irc.libera.#bcachefs" → finds irc.sock, returns ("irc.sock", "libera.#bcachefs")
+///
+/// If no daemon is running, tries to start one via the supervisor.
+fn find_daemon(path: &str) -> Result<(std::path::PathBuf, String)> {
+    let dir = channels_dir();
+
+    // Returns the sub-path after the matched prefix
+    let rest_after = |prefix: &str| -> String {
+        if prefix.len() < path.len() {
+            path[prefix.len() + 1..].to_string()
+        } else {
+            String::new()
+        }
+    };
+
+    // Walk from most-specific to least, looking for a socket
+    let mut prefix = path;
+    loop {
+        let sock = dir.join(format!("{}.sock", prefix));
+        if sock.exists() {
+            return Ok((sock, rest_after(prefix)));
+        }
+        match prefix.rfind('.') {
+            Some(pos) => prefix = &prefix[..pos],
+            None => break,
+        }
     }
-    Ok(sock)
+
+    // No running daemon found — register and start via supervisor
+    let top = path.split('.').next().unwrap_or(path);
+    let mut sup = crate::thalamus::supervisor::Supervisor::new();
+    sup.load_config();
+
+    if !sup.has_daemon(top) {
+        sup.add_daemon(top, crate::thalamus::supervisor::ChannelEntry {
+            binary: format!("consciousness-channel-{}", top),
+            enabled: true,
+            autostart: true,
+        });
+    }
+
+    sup.ensure_running();
+
+    // Wait for socket (up to 3 seconds)
+    let sock = dir.join(format!("{}.sock", top));
+    for _ in 0..30 {
+        if sock.exists() {
+            return Ok((sock, rest_after(top)));
+        }
+        std::thread::sleep(std::time::Duration::from_millis(100));
+    }
+
+    anyhow::bail!("no daemon for channel path: {}", path)
 }
 
 // ── Channel RPC ────────────────────────────────────────────────

src/thalamus/supervisor.rs

@@ -95,6 +95,22 @@ impl Supervisor {
         }
     }
 
+    /// Check if a daemon is in the config.
+    pub fn has_daemon(&self, name: &str) -> bool {
+        self.config.contains_key(name)
+    }
+
+    /// Add a daemon to the config and persist to channels.json5.
+    pub fn add_daemon(&mut self, name: &str, entry: ChannelEntry) {
+        self.config.insert(name.to_string(), entry);
+        let path = config_path();
+        if let Ok(json) = serde_json::to_string_pretty(&self.config) {
+            if let Err(e) = std::fs::write(&path, &json) {
+                error!("failed to write {}: {}", path.display(), e);
+            }
+        }
+    }
+
     /// Check if a daemon is alive by testing its socket.
     fn is_alive(name: &str) -> bool {
         let sock = channels_dir().join(format!("{}.sock", name));