ci(perf): enforce J1 ipcCallsToFirstCard and domMutationsToFirstCard

With the main window shown at did-finish-load, J1 takes one path on the
runner: three dispatched runs (36928706097, 36928716010, 36928725392)
read 15 bridge calls and 559 DOM mutations in all 18 iterations,
stable: true. Both become baselines (slack 0), and the Performance
journeys job checks them with check-journey-ratchet.mjs --only.

The journeys document records the race, its cause, the before/after
wall-clock and which other J1 counters are now stable.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tools/performance/journey-baselines.json

@@ -9,6 +9,24 @@
                 "updatedAt": "2026-10-01",
                 "evidencePr": 1775,
                 "measuredWith": "pnpm nx build web && pnpm run perf:initial-bytes"
+            },
+            "renderer.ipcCallsToFirstCard": {
+                "value": 15,
+                "unit": "calls",
+                "slack": 0,
+                "updatedAt": "2026-10-01",
+                "evidencePr": null,
+                "evidenceRun": "https://github.com/4gray/iptvnator/actions/runs/36928706097",
+                "measuredWith": "pnpm run perf:journeys (ubuntu-latest, xvfb), identical in 3 runs"
+            },
+            "renderer.domMutationsToFirstCard": {
+                "value": 559,
+                "unit": "mutations",
+                "slack": 0,
+                "updatedAt": "2026-10-01",
+                "evidencePr": null,
+                "evidenceRun": "https://github.com/4gray/iptvnator/actions/runs/36928706097",
+                "measuredWith": "pnpm run perf:journeys (ubuntu-latest, xvfb), identical in 3 runs"
             }
         }
     }