fix(config): warn and ignore unknown plugin entry keys

Prevent gateway startup failures when plugins.entries contains stale or removed plugin ids by downgrading unknown entry keys from validation errors to warnings.

Made-with: Cursor
(cherry picked from commit 34ef28cf63564159f3144cfb3b38756b468af4f0)

src/config/config.plugin-validation.test.ts

@@ -65,17 +65,18 @@ describe("config plugin validation", () => {
     }
   });
 
-  it("rejects missing plugin ids in entries", async () => {
+  it("warns for missing plugin ids in entries instead of failing validation", async () => {
     const home = await createCaseHome();
     const res = validateInHome(home, {
       agents: { list: [{ id: "pi" }] },
       plugins: { enabled: false, entries: { "missing-plugin": { enabled: true } } },
     });
-    expect(res.ok).toBe(false);
-    if (!res.ok) {
-      expect(res.issues).toContainEqual({
+    expect(res.ok).toBe(true);
+    if (res.ok) {
+      expect(res.warnings).toContainEqual({
         path: "plugins.entries.missing-plugin",
-        message: "plugin not found: missing-plugin",
+        message:
+          "plugin not found: missing-plugin (stale config entry ignored; remove it from plugins config)",
       });
     }
   });

src/config/validation.ts

@@ -315,7 +315,11 @@ function validateConfigObjectWithPluginsBase(
   }
 
   const { registry, knownIds, normalizedPlugins } = ensureRegistry();
-  const pushMissingPluginIssue = (path: string, pluginId: string) => {
+  const pushMissingPluginIssue = (
+    path: string,
+    pluginId: string,
+    opts?: { warnOnly?: boolean },
+  ) => {
     if (LEGACY_REMOVED_PLUGIN_IDS.has(pluginId)) {
       warnings.push({
         path,
@@ -323,6 +327,13 @@ function validateConfigObjectWithPluginsBase(
       });
       return;
     }
+    if (opts?.warnOnly) {
+      warnings.push({
+        path,
+        message: `plugin not found: ${pluginId} (stale config entry ignored; remove it from plugins config)`,
+      });
+      return;
+    }
     issues.push({
       path,
       message: `plugin not found: ${pluginId}`,
@@ -335,7 +346,8 @@ function validateConfigObjectWithPluginsBase(
   if (entries && isRecord(entries)) {
     for (const pluginId of Object.keys(entries)) {
       if (!knownIds.has(pluginId)) {
-        pushMissingPluginIssue(`plugins.entries.${pluginId}`, pluginId);
+        // Keep gateway startup resilient when plugins are removed/renamed across upgrades.
+        pushMissingPluginIssue(`plugins.entries.${pluginId}`, pluginId, { warnOnly: true });
       }
     }
   }