Address follow-up Copilot review feedback

Author: jasnsy

apps/server/src/provider/Layers/ProviderHealth.ts

@@ -49,6 +49,10 @@ class CopilotHealthProbeError extends Data.TaggedError("CopilotHealthProbeError"
   cause: unknown;
 }> {}
 
+function formatHealthProbeCause(cause: unknown): string {
+  return cause instanceof Error ? cause.message : String(cause);
+}
+
 // ── Pure helpers ────────────────────────────────────────────────────
 
 export interface CommandResult {
@@ -324,7 +328,7 @@ export const checkCopilotProviderStatus: Effect.Effect<ServerProviderStatus, nev
         checkedAt,
         message:
           error instanceof CopilotHealthProbeError
-            ? `Failed to start GitHub Copilot CLI: ${String(error.cause)}.`
+            ? `Failed to start GitHub Copilot CLI: ${formatHealthProbeCause(error.cause)}.`
             : "Failed to start GitHub Copilot CLI.",
       } satisfies ServerProviderStatus;
     }
@@ -367,7 +371,7 @@ export const checkCopilotProviderStatus: Effect.Effect<ServerProviderStatus, nev
         checkedAt,
         message:
           error instanceof CopilotHealthProbeError
-            ? `Could not verify GitHub Copilot authentication status: ${String(error.cause)}.`
+            ? `Could not verify GitHub Copilot authentication status: ${formatHealthProbeCause(error.cause)}.`
             : "Could not verify GitHub Copilot authentication status.",
       } satisfies ServerProviderStatus;
     }

apps/web/src/components/chat/composerProviderRegistry.tsx

@@ -121,13 +121,21 @@ const composerProviderRegistry: Record<ProviderKind, ProviderRegistryEntry> = {
     renderTraitsPicker: () => null,
   },
   copilot: {
-    getState: ({ modelOptions }) => ({
-      provider: "copilot",
-      promptEffort: modelOptions?.copilot?.reasoningEffort ?? null,
-      modelOptionsForDispatch: modelOptions?.copilot?.reasoningEffort
-        ? { copilot: { reasoningEffort: modelOptions.copilot.reasoningEffort } }
-        : undefined,
-    }),
+    getState: ({ modelOptions }) => {
+      const defaultPromptEffort = getDefaultReasoningEffort("copilot");
+      const promptEffort =
+        resolveReasoningEffortForProvider("copilot", modelOptions?.copilot?.reasoningEffort) ??
+        defaultPromptEffort;
+
+      return {
+        provider: "copilot",
+        promptEffort,
+        modelOptionsForDispatch:
+          promptEffort !== defaultPromptEffort
+            ? { copilot: { reasoningEffort: promptEffort } }
+            : undefined,
+      };
+    },
     renderTraitsMenuContent: () => null,
     renderTraitsPicker: () => null,
   },