fix: prefer the focused frame, bound model length, drop dead flag

test/settings.test.js

@@ -1,7 +1,7 @@
 import test from "node:test";
 import assert from "node:assert/strict";
 
-import { DEFAULT_SETTINGS } from "../lib/defaults.js";
+import { DEFAULT_SETTINGS, MAX_MODEL_CHARS } from "../lib/defaults.js";
 import { mergeSettings } from "../lib/settings.js";
 
 test("empty object yields the defaults", () => {
@@ -78,3 +78,17 @@ test("mergeSettings does not mutate DEFAULT_SETTINGS", () => {
   mergeSettings({ model: "mutated" });
   assert.equal(DEFAULT_SETTINGS.model, "");
 });
+
+// An unbounded model string can, on its own, push the finished URL over
+// MAX_URL_CHARS (lib/build-url.js), which silently drops `q` — the user's
+// selection vanishes with no signal. mergeSettings() must bound `model` the
+// same way it already bounds an out-of-range openIn: fall back to the default.
+test("a model at exactly MAX_MODEL_CHARS is accepted", () => {
+  const model = "m".repeat(MAX_MODEL_CHARS);
+  assert.equal(mergeSettings({ model }).model, model);
+});
+
+test("a model one character over MAX_MODEL_CHARS falls back to the default", () => {
+  const model = "m".repeat(MAX_MODEL_CHARS + 1);
+  assert.equal(mergeSettings({ model }).model, DEFAULT_SETTINGS.model);
+});