split fast dev test from the coverage gate run

`make test` is now the fast dev inner loop: no coverage, parallel
(--concurrency=12), ~21s warm (down from ~36s). Coverage moves to a new
`make test-coverage`, which push-check runs to feed coverage-gate. Drop the
separate test-a11y pass from push-check — the coverage run already executes
test/a11y. Both runs get --timeout 60s so a hung test fails fast instead of
wedging the runner ~10min and stalling the gate.

Measured: coverage is the floor (~36s) and concurrency-insensitive, so the
gate keeps coverage without --concurrency; only the no-coverage dev path
benefits from parallelism.

T-192.

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

ci/test.sh

@@ -1,10 +1,23 @@
 #!/usr/bin/env bash
 # Fast test layer — analyze + format + unit + widget + golden.
-# Runs in <60s on a warm cache. Called from `make test` and the
-# pre-push hook.
+#
+# Two modes (T-192):
+#   ci/test.sh              dev inner loop — NO coverage, parallel. ~20s warm.
+#   ci/test.sh --coverage   gate run — instrumented; writes coverage/lcov.info
+#                           for coverage-gate. ~36s (coverage is the floor and
+#                           is concurrency-insensitive, measured — so no
+#                           --concurrency here; it buys nothing).
+#
+# Both pass `--timeout 60s` so a hung test (a stray pumpAndSettle, or a
+# real-time deadlock) fails fast instead of wedging the runner for ~10 min and
+# stalling the pre-push gate. (Use the pumpAsync helper in tests; never
+# pumpAndSettle / Future.delayed(Duration.zero) inside testWidgets.)
 set -euo pipefail
 cd "$(dirname "$0")/.."
 
+coverage=0
+[[ "${1:-}" == "--coverage" ]] && coverage=1
+
 echo "==> flutter analyze"
 flutter analyze
 
@@ -14,5 +27,10 @@ dart format --set-exit-if-changed .
 echo "==> dart test (pty — unreliable under the flutter test runner)"
 dart test --tags pty test/pty/session_test.dart test/panes/registry_test.dart
 
-echo "==> flutter test --coverage (unit + widget + golden)"
-flutter test --coverage --exclude-tags pty
+if [[ "$coverage" == 1 ]]; then
+  echo "==> flutter test --coverage (gate; unit + widget + golden + a11y)"
+  flutter test --coverage --exclude-tags pty --timeout 60s
+else
+  echo "==> flutter test (dev; no coverage, parallel)"
+  flutter test --exclude-tags pty --concurrency=12 --timeout 60s
+fi