feat(queue): link rebuild queue entries to build log rows for live streaming

hive-c0re/src/rebuild_queue.rs

@@ -214,6 +214,15 @@ pub struct QueueEntry {
     /// most entries; serialised only when non-empty.
     #[serde(default, skip_serializing_if = "Vec::is_empty")]
     pub depends_on: Vec<u64>,
+    /// Row id of the associated `build_logs` entry (opened by the
+    /// lifecycle worker when `nixos-container update` starts). Set
+    /// shortly after `state` transitions to `Running`; `None` while
+    /// `Queued` or for entries that don't open a build log (`Restart`,
+    /// `PermChange` file-write phase, etc.). Links the queue card to
+    /// the live-streaming `/api/build-logs/id/{id}/stream` endpoint so
+    /// the operator can follow the nix build output in real time.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub build_log_id: Option<i64>,
 }
 
 /// How many terminal-state entries (`Done` / `Failed` / `Cancelled`)
@@ -429,6 +438,7 @@ impl RebuildQueue {
             step: None,
             perm_payload,
             depends_on,
+            build_log_id: None,
         };
         inner.entries.push_back(entry);
         // Wake the worker. `notify_one` is a no-op when there's no
@@ -521,6 +531,24 @@ impl RebuildQueue {
         true
     }
 
+    /// Link a `build_logs` row to a `Running` entry. Called by the
+    /// lifecycle worker when `nixos-container update` opens a build log
+    /// row so the dashboard can surface a "view logs" link while the
+    /// build is in flight. Returns `true` when the row was found and
+    /// the id was stored; `false` when the entry is no longer in the
+    /// queue or is not `Running`.
+    pub fn set_build_log_id(&self, id: u64, log_id: i64) -> bool {
+        let mut inner = self.inner.lock().expect("rebuild_queue mutex poisoned");
+        let Some(entry) = inner.entries.iter_mut().find(|e| e.id == id) else {
+            return false;
+        };
+        if entry.state != QueueState::Running {
+            return false;
+        }
+        entry.build_log_id = Some(log_id);
+        true
+    }
+
     /// Snapshot the queue for `/api/state` and `RebuildQueueChanged`.
     /// Cheap clone — entries are small (~hundreds of bytes each).
     pub fn snapshot(&self) -> Vec<QueueEntry> {