fix(auth): read enumerated issuers exactly, and stop the TUI tone going stale (#2144)

Copilot review round 4.

- `getTokens(url, issuer)` falls back to the legacy unkeyed slot when that
  issuer holds none — right for a connect, wrong for `collectGrants`, which
  labelled the fallback with the issuer it happened to be iterating and paired
  it with that issuer's credentials. During a partially migrated flow the clear
  could have sent an old, unbound token to a newly discovered authorization
  server. `OAuthStorage.getIssuerTokens` is the exact, no-fallback read; only
  the ctx-less read still falls back, which is the one place it belongs.
- The TUI's warning tone was sticky. It lived in its own state while ~30 call
  sites set ordinary OAuth notes without resetting it, so one revocation
  failure left every later "Authorization updated" yellow, across server
  switches. It is now DERIVED — `oauthMessageToneFor(message, warningText)` —
  so it cannot outlive the message that earned it, with nothing to remember to
  clear. Both setters stay plain `useState` setters: a `useCallback` wrapper
  would be a value `react-hooks/exhaustive-deps` demands in seven dependency
  arrays for an identity that never changes.
- Hook-level tests for the web wiring (previously missed): the per-server
  opt-out and the backend-proxied fetch are now asserted to reach
  `clearServerOAuthState`, so handing it the page-origin fetch — which a real
  authorization server's missing CORS headers would reject — fails a test.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0177mPHAdECD18nLLCTwR5rh
Signed-off-by: cliffhall <cliff@futurescale.com>

clients/tui/src/App.tsx

@@ -65,6 +65,7 @@ import {
   NodeOAuthStorage,
   runRunnerInteractiveOAuth,
 } from "@inspector/core/auth/node/index.js";
+import { oauthMessageToneFor } from "./oauthMessageTone.js";
 import { getTuiLogger } from "./logger.js";
 import { openUrl } from "./utils/openUrl.js";
 import {
@@ -161,13 +162,13 @@ function App({
     "idle" | "authenticating" | "error"
   >("idle");
   const [oauthMessage, setOauthMessage] = useState<string | null>(null);
-  // #2144: a revocation failure is a partial success — the local state really
-  // was cleared — so it is not an `error` status, but it must not read as an
-  // ordinary note either: the grant may still be live at the authorization
-  // server.
-  const [oauthMessageTone, setOauthMessageTone] = useState<"info" | "warning">(
-    "info",
-  );
+  // The tone is derived from the message rather than stored beside it, so it
+  // cannot go stale — see `oauthMessageToneFor` for why that matters here.
+  // Both stay plain `useState` setters on purpose: wrapping `setOauthMessage`
+  // in a `useCallback` would make it a value `react-hooks/exhaustive-deps`
+  // demands in seven dependency arrays, for an identity that never changes.
+  const [oauthWarningText, setOauthWarningText] = useState<string | null>(null);
+  const oauthMessageTone = oauthMessageToneFor(oauthMessage, oauthWarningText);
   const [oauthRevision, setOauthRevision] = useState(0);
   const [pendingStepUp, setPendingStepUp] = useState<{
     serverName: string;
@@ -956,12 +957,13 @@ function App({
       revoke: selectedServerEntry?.settings?.oauthRevokeOnClear !== false,
     });
     setOauthStatus("idle");
-    setOauthMessageTone(revocation.status === "failed" ? "warning" : "info");
-    setOauthMessage(
-      revocation.status === "failed"
-        ? `Cleared locally, but revoking the grant at the authorization server failed: ${revocation.detail}. It may still be valid there.`
-        : null,
-    );
+    if (revocation.status === "failed") {
+      const warning = `Cleared locally, but revoking the grant at the authorization server failed: ${revocation.detail}. It may still be valid there.`;
+      setOauthWarningText(warning);
+      setOauthMessage(warning);
+    } else {
+      setOauthMessage(null);
+    }
     setConnectError(null);
     if (inspectorStatus === "connected" || inspectorStatus === "connecting") {
       await disconnectInspector();