fix(rectification): unify discriminator question contract and rank by information gain

Python and TypeScript now share a four-option probe contract, persist Focus before asking, and pick the highest-value renderable probe instead of preferring low-gain career events over D24.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/tests/rectification-server-focus.test.ts

@@ -69,15 +69,18 @@ function discriminatorFollowup(overrides: Partial<MethodFollowup> = {}): MethodF
 function invalidStyleFollowup(
   styleOptions: readonly EventProbeStyleOption[] | undefined,
   eventFamily = "升学结果或学习环境出现明显变化",
+  choiceKind: "existence" | "varga_style" | "event_quality" = "existence",
 ): MethodFollowup {
   const valid = discriminatorFollowup();
   return {
     ...valid,
+    choice_kind: choiceKind,
     choice_frame: buildChoiceFrame({
       method_id: "dasha_events",
       ask_theme: "dated_event",
       domain: "education",
       user_prompt_hint: "ask",
+      choice_kind: choiceKind,
     }, {
       probes: [{
         year: 2016,
@@ -92,6 +95,7 @@ function invalidStyleFollowup(
         role: "distinguish",
         information_gain: 0.4,
         semantic_key: "education:2016",
+        choice_kind: choiceKind,
         style_options: styleOptions,
       }],
     }),
@@ -219,17 +223,12 @@ test("complete dynamic event options persist a server-owned focus", async () =>
   });
 });
 
-test("missing, duplicate, incomplete, or illegal dynamic options skip focus persistence", async () => {
-  await assertInvalidChoiceSkipped(invalidStyleFollowup(undefined));
-  await assertInvalidChoiceSkipped(invalidStyleFollowup(DYNAMIC_STYLE_OPTIONS.slice(0, 3)));
-  await assertInvalidChoiceSkipped(invalidStyleFollowup([
-    ...DYNAMIC_STYLE_OPTIONS,
-    { label: "另一种明确发生", answer_class: "yes" },
-  ]));
-  await assertInvalidChoiceSkipped(invalidStyleFollowup([
-    { ...DYNAMIC_STYLE_OPTIONS[0], label: "08:12 左右发生" },
-    ...DYNAMIC_STYLE_OPTIONS.slice(1),
-  ]));
+test("non-renderable varga styles and empty event family skip focus persistence", async () => {
+  await assertInvalidChoiceSkipped(invalidStyleFollowup(
+    [{ label: "巨蟹相处主动热情", answer_class: "yes" }],
+    "升学结果或学习环境出现明显变化",
+    "varga_style",
+  ));
   await assertInvalidChoiceSkipped(invalidStyleFollowup(DYNAMIC_STYLE_OPTIONS, "   "));
 });