fix(providers): disable test/usage buttons for Copilot and Codex OAuth cards

These OAuth providers ship with non-empty ANTHROPIC_BASE_URL, so the
isOfficialProvider() heuristic (which checks for a missing base URL)
returned false and left the health-check and usage-config buttons
enabled — inconsistent with other official OAuth cards. Extend the
button disabling logic at the call site with isCopilot / isCodexOauth,
matching the pattern already used for the quota footer branch above.

src/components/providers/ProviderCard.tsx

@@ -417,10 +417,14 @@ export function ProviderCard({
               onEdit={() => onEdit(provider)}
               onDuplicate={() => onDuplicate(provider)}
               onTest={
-                onTest && !isOfficial ? () => onTest(provider) : undefined
+                onTest && !isOfficial && !isCopilot && !isCodexOauth
+                  ? () => onTest(provider)
+                  : undefined
               }
               onConfigureUsage={
-                isOfficial ? undefined : () => onConfigureUsage(provider)
+                isOfficial || isCopilot || isCodexOauth
+                  ? undefined
+                  : () => onConfigureUsage(provider)
               }
               onDelete={() => onDelete(provider)}
               onRemoveFromConfig={