feat(#2591): add GET /api/build-log/<node_id> {,/raw} query endpoints

The raw-graph wire drops the inline build_log_id; the client fetches a
node's captured output on demand. Two handlers resolve node id -> log-row
id (JobQueue::build_log_id_of, now keyed by the wire u64) then delegate to
the existing get_full / raw handlers: /api/build-log/<node_id> serves the
BuildLogFull JSON ({stdout, stderr} + header), /raw serves text/plain.
404 when the node has no linked log.

hive-c0re/src/dashboard/build_logs.rs

@@ -90,6 +90,42 @@ pub(super) async fn get_build_log_full(
     }
 }
 
+/// `GET /api/build-log/{node_id}` — the build log for a **queue node**,
+/// resolved node id → log-row id → full log. Same `BuildLogFull` JSON
+/// (`stdout` / `stderr` + header) as `get_build_log_full`; HTTP 404 when the
+/// node has no linked log (the client gates the request on `NodeView.has_log`,
+/// but a vacuum race can still 404). This is the on-demand log fetch the
+/// raw-graph dashboard uses instead of an inline `build_log_id` on the wire.
+pub(super) async fn get_build_log_for_node(
+    State(state): State<AppState>,
+    AxumPath(node_id): AxumPath<u64>,
+) -> Response {
+    match state.coord.job_queue.build_log_id_of(node_id) {
+        Some(log_id) => get_build_log_full(State(state), AxumPath(log_id)).await,
+        None => (
+            StatusCode::NOT_FOUND,
+            format!("node #{node_id} has no build log"),
+        )
+            .into_response(),
+    }
+}
+
+/// `GET /api/build-log/{node_id}/raw` — the node's build log as `text/plain`
+/// for download (delegates to `get_build_log_raw` after resolving the node id).
+pub(super) async fn get_build_log_raw_for_node(
+    State(state): State<AppState>,
+    AxumPath(node_id): AxumPath<u64>,
+) -> Response {
+    match state.coord.job_queue.build_log_id_of(node_id) {
+        Some(log_id) => get_build_log_raw(State(state), AxumPath(log_id)).await,
+        None => (
+            StatusCode::NOT_FOUND,
+            format!("node #{node_id} has no build log"),
+        )
+            .into_response(),
+    }
+}
+
 /// JSON frame sent on the `/api/build-logs/id/{id}/stream` SSE channel.
 /// `stdout_append` / `stderr_append` carry only the new bytes since the
 /// last frame; `done = true` means the build finished and the stream

hive-c0re/src/dashboard/mod.rs

@@ -100,6 +100,14 @@ pub async fn serve(
         )
         .route("/api/audit-log", get(misc_api::api_audit_log))
         .route("/api/build-logs", get(build_logs::get_build_logs_all))
+        .route(
+            "/api/build-log/{node_id}",
+            get(build_logs::get_build_log_for_node),
+        )
+        .route(
+            "/api/build-log/{node_id}/raw",
+            get(build_logs::get_build_log_raw_for_node),
+        )
         .route(
             "/api/build-logs/{agent}",
             get(build_logs::get_build_logs_agent),