feat(telemetry): the reasoning stream actually streams

`agent.reasoning.delta` and `agent.tool.call` have been declared in the taxonomy
and listened for by the command centre since it shipped — and NOTHING ever
emitted them. The world feed emitted five types; neither was among them, so
REASONING STREAM could not populate no matter what an agent did.

The feed is a database poll, not a push bus, so a live card can only show what
was persisted. The worker already holds each step's output text and the claw
that produced it, so it records a `reasoning` mission_event (truncated — the
card renders a tail, not a transcript, and mission_events is capped per phase),
and the feed emits it forward from a cursor that starts at the current max so a
page load streams rather than replaying history.

`tool.call` is emitted from the same place. On the container tier it will stay
empty, and that is correct rather than broken: those agents are tool-free behind
the §15 door. Tool lines appear where agents actually hold tools.

Verified on a live mission: agent.reasoning.delta observed on /api/world/live
carrying the agent's own text, keyed by agentId.

Co-Authored-By: Claude Opus 5 <[email protected]>

crates/cm-api/src/routes/world.rs

@@ -77,11 +77,7 @@ struct MissionRow {
     agent_id: Option<String>,
 }
 
-async fn world_missions(
-    pool: &PgPool,
-    ws: WorkspaceId,
-    only: Option<Uuid>,
-) -> Vec<MissionRow> {
+async fn world_missions(pool: &PgPool, ws: WorkspaceId, only: Option<Uuid>) -> Vec<MissionRow> {
     let rows = sqlx::query(
         "SELECT m.id::text          AS mission_id,
                 m.title              AS title,
@@ -416,11 +412,7 @@ fn benchmark_note(delta: &serde_json::Value) -> Option<String> {
 
 /// Agents that execute a phase of this kind, via the purposes the phase runner
 /// itself uses. Returns empty for a teamless (microVM) mission.
-async fn phase_agents(
-    pool: &PgPool,
-    mission_id: &str,
-    kind: &str,
-) -> Vec<String> {
+async fn phase_agents(pool: &PgPool, mission_id: &str, kind: &str) -> Vec<String> {
     let Ok(mid) = Uuid::parse_str(mission_id) else {
         return Vec::new();
     };
@@ -751,6 +743,10 @@ pub async fn world_live(
         // Audit-log cursor for edge-initiated inter-agent events (delegation,
         // A2A) that bypass the run loop. -1 until seeded on the first pass.
         let mut audit_cursor: i64 = -1;
+        // Cursor over mission_events for the per-agent LIVE column. Starts at
+        // -1 and jumps to the current max on first sight, so a page load
+        // streams forward instead of replaying every past turn.
+        let mut agent_ev_cursor: i64 = -1;
         // Track the brain-file size we last announced per agent so we only
         // emit `agent.memory` when the file has actually grown (or shrunk).
         // On first seed we still emit — the World engine needs the initial
@@ -1106,6 +1102,68 @@ pub async fn world_live(
                 }));
             }
 
+            // Per-agent LIVE column: REASONING STREAM + tool lines.
+            //
+            // These two taxonomy types were declared and listened for since the
+            // command centre shipped, and NOTHING ever emitted them — the cards
+            // could not populate no matter what an agent did. mission_events is
+            // the durable source: `reasoning` rows carry the agent's own step
+            // output, `tool.call` rows its actions.
+            //
+            // NOTE: on the container tier `tool.call` legitimately stays empty —
+            // those agents are tool-free behind the §15 door. Reasoning flows on
+            // every tier; tool lines appear where agents actually hold tools.
+            if agent_ev_cursor < 0 {
+                agent_ev_cursor = sqlx::query_scalar(
+                    "SELECT coalesce(max(id), 0) FROM mission_events",
+                )
+                .fetch_one(&pool)
+                .await
+                .unwrap_or(0);
+            } else {
+                let rows = sqlx::query(
+                    "SELECT e.id, e.agent_id, e.kind, e.target, e.detail
+                       FROM mission_events e
+                       JOIN missions m ON m.id = e.mission_id
+                      WHERE m.workspace_id = $1
+                        AND e.id > $2
+                        AND e.agent_id IS NOT NULL
+                        AND e.kind IN ('reasoning', 'tool.call')
+                      ORDER BY e.id
+                      LIMIT 200",
+                )
+                .bind(ws.as_uuid())
+                .bind(agent_ev_cursor)
+                .fetch_all(&pool)
+                .await
+                .unwrap_or_default();
+                for r in &rows {
+                    let eid: i64 = r.get("id");
+                    agent_ev_cursor = agent_ev_cursor.max(eid);
+                    let agent_id: Option<uuid::Uuid> = r.get("agent_id");
+                    let Some(agent_id) = agent_id else { continue };
+                    let kind: String = r.get("kind");
+                    let detail: serde_json::Value = r.get("detail");
+                    let target: Option<String> = r.get("target");
+                    if kind == "tool.call" {
+                        yield sse("agent.tool.call", json!({
+                            "agentId": agent_id.to_string(),
+                            "tool": target.clone().unwrap_or_default(),
+                            "target": detail.get("path").and_then(|v| v.as_str()),
+                        }));
+                    } else {
+                        let text = detail.get("text").and_then(|v| v.as_str()).unwrap_or("");
+                        if !text.is_empty() {
+                            yield sse("agent.reasoning.delta", json!({
+                                "agentId": agent_id.to_string(),
+                                "text": text,
+                                "channel": "say",
+                            }));
+                        }
+                    }
+                }
+            }
+
             // Workspace-wide telemetry (top-bar pills / Observe system strip).
             yield sse(
                 "telemetry",
@@ -1274,7 +1332,10 @@ mod mission_feed_tests {
         // finds. Written whole, the test fails on itself — which it did, and
         // which is the same self-match that makes `pkill -f <pattern>` kill the
         // shell carrying the pattern.
-        let needle = concat!("SELECT checkpoint FROM topology_", "runs WHERE id = $1::uuid");
+        let needle = concat!(
+            "SELECT checkpoint FROM topology_",
+            "runs WHERE id = $1::uuid"
+        );
         assert!(
             !src.contains(needle),
             "the checkpoint tail is keyed on an agent_runs id and cannot match a \