perf: avoid no-op plugin auto-enable scans

src/config/plugin-auto-enable.apply.ts

@@ -18,6 +18,15 @@ export function materializePluginAutoEnableCandidates(params: {
 }): PluginAutoEnableResult {
   const env = params.env ?? process.env;
   const config = params.config ?? {};
+  const entries = config.plugins?.entries;
+  const hasRestrictiveAllowlistWithEntries =
+    Array.isArray(config.plugins?.allow) &&
+    config.plugins.allow.length > 0 &&
+    entries !== undefined &&
+    typeof entries === "object";
+  if (params.candidates.length === 0 && !hasRestrictiveAllowlistWithEntries) {
+    return { config, changes: [], autoEnabledReasons: {} };
+  }
   const manifestRegistry = resolvePluginAutoEnableManifestRegistry({
     config,
     env,

src/config/plugin-auto-enable.shared.ts

@@ -1,9 +1,6 @@
 import { collectConfiguredAgentHarnessRuntimes } from "../agents/harness-runtimes.js";
 import { normalizeProviderId } from "../agents/provider-id.js";
-import {
-  hasPotentialConfiguredChannels,
-  listPotentialConfiguredChannelPresenceSignals,
-} from "../channels/config-presence.js";
+import { listPotentialConfiguredChannelPresenceSignals } from "../channels/config-presence.js";
 import { getChatChannelMeta, normalizeChatChannelId } from "../channels/registry.js";
 import {
   type PluginManifestRecord,
@@ -493,7 +490,7 @@ export function configMayNeedPluginAutoEnable(
   if (hasConfiguredPluginConfigEntry(cfg)) {
     return true;
   }
-  if (hasPotentialConfiguredChannels(cfg, env, { includePersistedAuthState: false })) {
+  if (collectConfiguredChannelIds(cfg, env).length > 0) {
     return true;
   }
   if (hasConfiguredProviderModelOrHarness(cfg, env)) {