fix(gate): stop injecting the redundant Altro option on select gates

buildSelectRequest injected an `altroOption` ({id:"other", opens:freetext}) into the
select descriptor, but SelectWidget/MultiselectWidget never route option.opens — so it
rendered as an inert "Altro — specifica…" button next to the working reserved
"Other — specify" control (which now owns free-text since the reviewer-gate-ux fix).
Remove the injection, the now-unused altroOption()/ALTRO_LABEL, and the unused
allow_other flag from both builders (no frontend consumer). Free-text stays offered on
every gate via the reserved "Other" control. The ArtifactGateWidget opens/LinkageHost
linkage (reject-with-reason capability) is intentionally kept — it is a separate,
tested feature, not the injected duplicate.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

harness/.pi/extensions/gate/__tests__/builders.test.js

@@ -33,20 +33,17 @@ test("select F1 matches golden shape", () => {
   assert.equal(result.type, "ui_request");
   assert.equal(result.schema_version, 1);
   assert.deepEqual(result.reserved, g.reserved); // back/exit/other framework hatches
-  assert.deepEqual(
-    result.options.filter((o) => o.id !== "other"),
-    g.options.filter((o) => o.id !== "other"),
-  );
+  assert.deepEqual(result.options, g.options);
 });
 
-test("select always carries the Altro escape hatch with freetext linkage", () => {
+test("select no longer injects an Altro option (free-text is the reserved 'Other' control)", () => {
   const result = buildSelectRequest({
     id: "u", phase: "F1", title: "x",
     options: [{ id: "a", label: "A" }],
   });
-  const other = result.options.find((o) => o.id === "other");
-  assert.ok(other, "Altro option must always be present");
-  assert.equal(other.opens.widget, "freetext");
+  assert.equal(result.options.find((o) => o.id === "other"), undefined, "no injected Altro option");
+  assert.ok(!("allow_other" in result), "the unused allow_other flag is gone");
+  assert.deepEqual(result.reserved, ["back", "exit", "other"], "Altro still offered via the reserved control");
 });
 
 test("select surfaces a recommended marker when given", () => {
@@ -70,6 +67,7 @@ test("multiselect F4 matches golden + carries content + allowEmpty", () => {
   const g = golden("multiselect_F4.json");
   assert.equal(result.widget, "multiselect");
   assert.equal(result.allow_empty, false);
+  assert.ok(!("allow_other" in result), "the unused allow_other flag is gone");
   assert.ok("content" in result);
   assert.deepEqual(result.reserved, g.reserved);
 });

harness/.pi/extensions/gate/__tests__/golden/multiselect_F4.json

@@ -6,7 +6,6 @@
   "widget": "multiselect",
   "title": "Tabelle",
   "allow_empty": false,
-  "allow_other": true,
   "options": [],
   "selected": [],
   "content": { "candidates": [] },

harness/.pi/extensions/gate/__tests__/golden/select_F1.json

@@ -6,12 +6,10 @@
   "widget": "select",
   "title": "Disambigua 'ablazione'",
   "intro": null,
-  "allow_other": true,
   "recommended": null,
   "options": [
     { "id": "o1", "label": "procedura" },
-    { "id": "o2", "label": "patologia" },
-    { "id": "other", "label": "Altro — specifica…", "opens": { "widget": "freetext", "title": "Specifica…" } }
+    { "id": "o2", "label": "patologia" }
   ],
   "reserved": ["back", "exit", "other"]
 }

harness/.pi/extensions/gate/builders.js

@@ -15,7 +15,6 @@
 const SCHEMA_VERSION = 1;
 const RESERVED = ["back", "exit", "other"];
 
-const ALTRO_LABEL = "Altro — specifica…";
 const VALID_ACTION_KINDS = new Set(["confirm", "approve_reject", "view_only"]);
 const VALID_INFO_LEVELS = new Set(["info", "warning", "error"]);
 
@@ -33,21 +32,12 @@ function requireArray(value, name, ctx) {
   return value;
 }
 
-// An "other" option that opens a freetext child widget. Always present on
-// blocking pick widgets so the reviewer is never trapped in the listed options.
-function altroOption() {
-  return {
-    id: "other",
-    label: ALTRO_LABEL,
-    opens: { widget: "freetext", title: "Specifica…" },
-  };
-}
-
-// Build a `select` ui_request (single-pick). Reserved hatches (Altro/Back/Exit)
-// are injected; Altro carries the freetext linkage (§4.2). `recommended` is the
-// id of the option to highlight as "(consigliato)".
+// Build a `select` ui_request (single-pick). The framework escape hatches
+// (Back/Exit/Other) come from `reserved` (rendered by ReservedControls, which owns
+// the free-text linkage on "Other"). `recommended` is the id of the option to
+// highlight as "(consigliato)".
 function buildSelectRequest({
-  id, phase, title, options, intro = null, allowOther = true, recommended = null,
+  id, phase, title, options, intro = null, recommended = null,
 }) {
   requireString(title, "title", "select");
   const opts = requireArray(options, "options", "select");
@@ -59,9 +49,8 @@ function buildSelectRequest({
     widget: "select",
     title,
     intro,
-    allow_other: allowOther,
     recommended,
-    options: allowOther ? [...opts, altroOption()] : [...opts],
+    options: [...opts],
     reserved: RESERVED,
   };
   return out;
@@ -71,7 +60,7 @@ function buildSelectRequest({
 // context (e.g. schema candidates); `selected` the pre-checked option ids;
 // `allowEmpty:false` with zero options is a broken widget and throws.
 function buildMultiselectRequest({
-  id, phase, title, options, content = null, selected = [], allowEmpty = false, allowOther = true,
+  id, phase, title, options, content = null, selected = [], allowEmpty = false,
 }) {
   requireString(title, "title", "multiselect");
   const opts = requireArray(options, "options", "multiselect");
@@ -88,7 +77,6 @@ function buildMultiselectRequest({
     widget: "multiselect",
     title,
     allow_empty: allowEmpty,
-    allow_other: allowOther,
     options: [...opts],
     selected: [...selected],
     content,