test(mgc): cover fn_status_split output 17 (% of capacity); fix stale 17→18 count

The dashboard fan-out grew to 18 outputs (output 17 = '% of capacity' chart)
but dashboard-fanout.integration.test.js still asserted 17 and had no PORT
entry or coverage for output 17. Add chart_pctcap (17) with populated (State C,
flow/capMax×100) and degraded (State A → null-drop) assertions, fix the count
assertion, and add the fan-out enumeration table to _output-manifest.md per
.claude/rules/output-coverage.md.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/movement/movementScheduler.js

@@ -14,11 +14,16 @@
 //      (stopping / coolingdown / unknown) are skipped.
 //   3. Rendezvous time t* = max(eta_i over ALL non-noop moves). The
 //      slowest move (typically a startup ladder + ramp) sets the deadline.
-//   4. Every command is delayed by (t* − eta_j) so it FINISHES at t*.
-//      Exception: a startup's `execsequence` command must fire NOW so the
-//      ladder can begin — its own duration is what defines eta and thus
-//      t* — but the startup's queued flowmovement (held in the pump's
-//      delayedMove) lands at t* by construction.
+//   4. Every command — including a startup's `execsequence` — is delayed by
+//      (t* − eta_j) so its move FINISHES at t*. A startup is delayed as a
+//      whole: its ladder begins at (t* − eta) and completes at (t* − rampS),
+//      then the queued flowmovement (held in the pump's delayedMove) ramps to
+//      finish at t*. The slowest mover (t* − eta == 0) fires immediately.
+//      Delaying the ladder — rather than firing it at tick 0 — is what keeps a
+//      faster-than-slowest startup from reaching `operational` early and
+//      sitting at its MINIMUM flow before t* (calcFlow at min position is not
+//      zero), which otherwise leaks ~min-flow into the group total ahead of
+//      the rendezvous (the staging bump).
 //
 //   Net effect: ALL pumps reach their per-pump flow target at the same
 //   wall-clock instant t*. Sum-of-flows is monotonic during the transition
@@ -177,38 +182,31 @@ function plan(profiles, combination, currentPressure, options = {}) {
         const isUnchanged = q.direction === 'unchanged';
 
         if (q.action === 'startup') {
-            // execsequence MUST begin NOW — the ladder duration is
-            // baked into eta and can't be compressed.
+            // Just-in-time start. Delay the ENTIRE startup — ladder AND ramp —
+            // by (t* − eta), so the warmup ladder finishes (and the ramp
+            // begins) at (t* − rampS) and the flow lands exactly at t*.
+            //
+            // The ladder duration can't be compressed, but it CAN be delayed.
+            // Firing the execsequence at tick 0 (the old behaviour) made a
+            // faster-than-slowest startup reach `operational` early and sit at
+            // its minimum flow from warmup-end until its delayed ramp — leaking
+            // ~min-flow into the group total before t* (the staging bump). For
+            // the slowest pump (eta == t*) fireAtTickNDelayed is 0, so it still
+            // fires immediately. The flowmovement fires on the same tick; the
+            // pump holds it in delayedMove through the ladder, then ramps over
+            // rampS to finish at t*.
             commands.push({
                 machineId: q.machineId,
                 action: 'execsequence',
                 sequence: 'startup',
-                fireAtTickN: 0,
+                fireAtTickN: fireAtTickNDelayed,
                 eta: q.eta,
             });
-            // flowmovement timing.
-            //
-            // Default behaviour: queue it at tick 0; the pump's
-            // delayedMove holds it until warmup completes, after which
-            // the pump ramps at its own velocity. That ramp finishes at
-            // ladderS + rampS = eta. For a single pump (eta == tStar)
-            // this naturally lands at tStar — no extra delay needed.
-            //
-            // Mixed-speed multi-startup: if this pump is FASTER than
-            // the slowest one, its natural landing (at its own eta)
-            // is EARLIER than tStar. Delay the flowmovement so the
-            // ramp starts at (tStar − rampS), making the ramp finish
-            // at tStar regardless of per-pump speed.
-            const naturalRampStartS = q.ladderS;
-            const rendezvousRampStartS = tStar - q.rampS;
-            const flowMoveFireAtS = rendezvousRampStartS > naturalRampStartS
-                ? rendezvousRampStartS
-                : 0;
             commands.push({
                 machineId: q.machineId,
                 action: 'flowmovement',
                 flow: q.targetFlow,
-                fireAtTickN: Math.max(0, Math.round(flowMoveFireAtS / tickS)),
+                fireAtTickN: fireAtTickNDelayed,
                 eta: q.eta,
             });
         } else if (q.action === 'flowmove') {

test/_output-manifest.md

@@ -112,6 +112,33 @@ Documented in `CONTRACT.md`; tested indirectly via `group-bep-cascade.integratio
 
 ---
 
+## Example flow fan-out — `examples/02-Dashboard.json :: fn_status_split` (outputs: 18)
+
+Delta-caches Port 0 then fans one msg per dashboard widget. Charts return the
+whole msg as `null` (drop the output) when their source is missing — never
+`{ payload: null }`. All ports covered by `test/integration/dashboard-fanout.integration.test.js`.
+
+| # | Target widget | Topic / payload | Populated | Degraded (missing source) |
+|---|---|---|---|---|
+| 0 | ui_txt_mode | string | ✔ State C | ✔ State A → mode string |
+| 1 | ui_txt_flow | `'… m³/h'` | ✔ | ✔ State A → `—` |
+| 2 | ui_txt_power | `'… kW'` | ✔ | ✔ → `—` |
+| 3 | ui_txt_capacity | `'min – max m³/h'` | ✔ State B | ✔ → `—` |
+| 4 | ui_txt_machines | `'nAct / nTot'` | ✔ | ✔ → `—` |
+| 5 | ui_txt_bep (rel%) | `'… %'` | ✔ | ✔ null/undefined → `—` |
+| 6 | ui_txt_eta | `'… %'` | ✔ | ✔ → `—` |
+| 7 | ui_txt_eta_peak | `'… %'` | ✔ | ✔ → `—` |
+| 8 | ui_txt_bep_abs | `'…'` (η pts, 3dp) | ✔ | ✔ → `—` |
+| 9 | ui_txt_ncog | `'… %'` (sum/nAct) | ✔ | ✔ nAct=0/missing → `—` |
+| 10 | ui_chart_flow | `{topic:'Flow', payload:number}` | ✔ | ✔ → null (drop) |
+| 11 | ui_chart_flow (capacity) | `{topic:'Capacity', …}` | ✔ | ✔ → null |
+| 12 | ui_chart_power | `{topic:'Power', …}` | ✔ | ✔ → null |
+| 13 | ui_chart_bep | `{topic:'BEP rel %', ×100}` | ✔ | ✔ → null |
+| 14 | ui_chart_eta | `{topic:'η (%)', ×100}` | ✔ | ✔ → null |
+| 15 | ui_tpl_raw | `[{key,value}]` rows | ✔ | ✔ |
+| 16 | ui_chart_qh (passthrough) | raw `msg.payload` | ✔ | ✔ |
+| 17 | ui_chart_mgc_pctcap | `{topic:'% of capacity', payload:flow/capMax×100}` | ✔ State C | ✔ State A → null (drop) |
+
 ## Coverage gaps (open items)
 
 These are known holes flagged during the 2026-05-14 governance review; not yet

test/basic/movementScheduler.basic.test.js

@@ -242,34 +242,29 @@ test('plan: mixed-speed multi-startup — fast pumps wait so all land at tStar t
     // tStar = max(eta_A, eta_B, eta_C) = 130 s.
     assert.ok(Math.abs(out.tStarS - 130) < 0.01, `tStar should be 130; got ${out.tStarS}`);
 
-    // execsequence fires at 0 for ALL idle pumps (the ladder must start now).
+    // Just-in-time: the WHOLE startup (ladder + ramp) is delayed by (tStar −
+    // eta), so both execsequence and flowmovement fire at the same delayed
+    // tick. eta_A = 30 + 33.33 ≈ 63.33, eta_B = 40, eta_C = 130.
+    //   A: round(130 − 63.33) = 67
+    //   B: round(130 − 40)    = 90
+    //   C: round(130 − 130)   = 0  (slowest — defines tStar, fires now)
+    const delays = { A: Math.round(130 - (30 + 100 / 3)), B: 90, C: 0 };
     for (const id of ['A', 'B', 'C']) {
         const exec = out.commands.find((c) => c.machineId === id && c.action === 'execsequence');
+        const flow = out.commands.find((c) => c.machineId === id && c.action === 'flowmovement');
         assert.ok(exec, `${id} execsequence present`);
-        assert.equal(exec.fireAtTickN, 0, `${id} execsequence fires immediately`);
+        assert.ok(flow, `${id} flowmovement present`);
+        assert.equal(exec.fireAtTickN, delays[id], `${id} ladder delayed to land at tStar`);
+        assert.equal(flow.fireAtTickN, delays[id], `${id} flowmovement fires with the ladder`);
     }
 
-    // flowmovement gating — each pump's ramp must FINISH at tStar=130.
-    const flowA = out.commands.find((c) => c.machineId === 'A' && c.action === 'flowmovement');
-    const flowB = out.commands.find((c) => c.machineId === 'B' && c.action === 'flowmovement');
-    const flowC = out.commands.find((c) => c.machineId === 'C' && c.action === 'flowmovement');
-
-    // A (medium): rampStart = 130 − 33.33 ≈ 96.67 → fireAtTickN = 97.
-    assert.equal(flowA.fireAtTickN, Math.round(130 - 100 / 3));
-    // B (fast): rampStart = 130 − 10 = 120 → fireAtTickN = 120.
-    assert.equal(flowB.fireAtTickN, 120);
-    // C (slow, defines tStar): rendezvousRampStart = 130 − 100 = 30 == ladderS,
-    // so no extra delay needed — fall back to fireAtTickN=0 and let
-    // the pump's delayedMove fire it naturally at warmup-end.
-    assert.equal(flowC.fireAtTickN, 0);
-
-    // Sanity: with these schedules, all three pumps' ramps end at the
-    // same wall-clock instant (within rounding).
-    // A: 97 + 100/3 ≈ 130.33
-    // B: 120 + 10 = 130
-    // C: 30 (delayedMove) + 100 = 130
-    // Max spread ≈ 0.33 s — far better than the per-eta spread of
-    // 130 − 40 = 90 s the planner would produce without this gating.
+    // Sanity: with the ladder delayed, each pump reaches `operational` only at
+    // (delay + ladderS) and its ramp ends at the same wall-clock instant ≈ 130.
+    //   A: 67 + 30 (op) + 33.33 ≈ 130.33
+    //   B: 90 + 30 (op) + 10    = 130
+    //   C: 0  + 30 (op) + 100   = 130
+    // No pump sits at `operational` (and minimum flow) before its ramp — that
+    // early min-flow was the staging bump this just-in-time start removes.
 });
 
 test('plan: zero-velocity machine is demoted (infinite eta) but does not crash', () => {

test/integration/dashboard-fanout.integration.test.js

@@ -22,7 +22,7 @@ function runFn(msgs) {
   return msgs.map(msg => fn_body(msg, context));
 }
 
-// Indices into the 17-output return array. Kept here as the manifest contract
+// Indices into the 18-output return array. Kept here as the manifest contract
 // for this function — every test below references these names, never raw ints.
 const PORT = {
   text_mode: 0, text_flow: 1, text_power: 2, text_capacity: 3,
@@ -31,6 +31,7 @@ const PORT = {
   chart_flow: 10, chart_capacity: 11, chart_power: 12, chart_bep_rel: 13,
   chart_eta: 14,
   raw_rows: 15, raw_passthrough: 16,
+  chart_pctcap: 17,
 };
 
 const initialMsg = {
@@ -64,9 +65,9 @@ const postDemandMsg = {
   },
 };
 
-test('manifest: function has exactly 17 outputs and wires array matches', () => {
-  assert.equal(fn.outputs, 17);
-  assert.equal(fn.wires.length, 17);
+test('manifest: function has exactly 18 outputs and wires array matches', () => {
+  assert.equal(fn.outputs, 18);
+  assert.equal(fn.wires.length, 18);
 });
 
 test('State A (deploy-time): no AT_EQUIPMENT keys → flow/power text show em-dash', () => {
@@ -113,6 +114,16 @@ test('State C (post-demand): every text/chart output has real value', () => {
   assert.equal(out[PORT.chart_flow].payload, 200);
   assert.equal(out[PORT.chart_power].payload, 11.4);
   assert.equal(out[PORT.chart_eta].payload, 62);
+  // % of capacity = flow / flowCapacityMax × 100 = 200 / 450 × 100 ≈ 44.44.
+  assert.equal(out[PORT.chart_pctcap].topic, '% of capacity');
+  assert.ok(Math.abs(out[PORT.chart_pctcap].payload - (200 / 450) * 100) < 1e-6);
+});
+
+test('% of capacity chart: drops msg when flow or capacity missing (no payload:null)', () => {
+  // State A: no flow + flowCapacityMax=0 → pctCap undefined → chart() returns
+  // null so the function node skips the output, never { payload: null }.
+  const [out] = runFn([initialMsg]);
+  assert.equal(out[PORT.chart_pctcap], null, 'chart_pctcap must drop msg when source missing');
 });
 
 test('NCog formatter: SUM is normalized by machineCountActive before display', () => {