ci: consolidate gates on large runners

scripts/run-gates.ts

@@ -15,6 +15,7 @@ import { selectStaticGates } from './static-shards.ts'
 
 type Mode =
   | 'ci-primary'
+  | 'ci-primary-prebuilt'
   | 'ci-static'
   | 'ci-lint'
   | 'ci-coverage'
@@ -87,6 +88,7 @@ if (results.some(result => result.status === 'failed' || result.status === 'skip
 function parseMode(raw: string | undefined): Mode {
   switch (raw) {
     case 'ci-primary':
+    case 'ci-primary-prebuilt':
     case 'ci-static':
     case 'ci-lint':
     case 'ci-coverage':
@@ -100,7 +102,7 @@ function parseMode(raw: string | undefined): Mode {
       return raw
     default:
       throw new Error(
-        `run-gates: expected mode ci-primary | ci-static | ci-lint | ci-coverage | ci-snapshot | ci-artifacts | ci-windows-blocking | ci-windows-observational | node-compat | pre-push | doc-sync, got ${JSON.stringify(raw)}.`,
+        `run-gates: expected mode ci-primary | ci-primary-prebuilt | ci-static | ci-lint | ci-coverage | ci-snapshot | ci-artifacts | ci-windows-blocking | ci-windows-observational | node-compat | pre-push | doc-sync, got ${JSON.stringify(raw)}.`,
       )
   }
 }
@@ -166,6 +168,8 @@ function gatesForMode(selected: Mode): Gate[] {
   switch (selected) {
     case 'ci-primary':
       return ciPrimaryGates()
+    case 'ci-primary-prebuilt':
+      return ciPrimaryPrebuiltGates()
     case 'ci-static':
       return ciStaticGates()
     case 'ci-lint': {
@@ -246,6 +250,14 @@ function ciPrimaryGates(): Gate[] {
   ]
 }
 
+function ciPrimaryPrebuiltGates(): Gate[] {
+  return ciPrimaryGates()
+    .filter(gate => gate.id !== 'build')
+    .map(gate => gate.needs?.includes('build') === true
+      ? { ...gate, needs: gate.needs.filter(id => id !== 'build') }
+      : gate)
+}
+
 function ciStaticGates(): Gate[] {
   const gates = [
     pnpmScript('runtime-closure', 'verify-runtime-closure', { label: 'runtime closure' }),