Add Jev screenshot input and a stepwise controller

Benchmark variants now run interleaved per scenario. Adding the page
screenshot to the no-gate controller lowered verified passes from
109/150 to 79/150 on Jev 1.14. The stepwise controller (settling,
compact history, per-field values, finish vs stop, no-op skipping,
ordered aim progress, Escape) reached 150/150 with screenshots and
149/150 without. Three verifiers now check outcomes rather than the
final page, and the fault matrix shows no pass with a broken outcome.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Author: ostenbom

package.json

@@ -55,6 +55,7 @@
 		"oxfmt": "0.68.0",
 		"oxlint": "1.83.0",
 		"playwright-opentelemetry": "^0.13.0",
+		"sharp": "0.35.4",
 		"tsx": "^4.23.15",
 		"typescript": "^7.0.2"
 	},

pnpm-lock.yaml

@@ -1,5 +1,5 @@
 import { expect, test } from "bun:test";
-import { actionCode, candidates } from "./jev-benchmark";
+import { actionCode, candidates, select } from "./jev-benchmark";
 
 test("builds bounded actions from an accessibility observation", () => {
 	const actions = candidates(
@@ -37,3 +37,56 @@ test("keeps action arguments literal", () => {
 		}),
 	).toThrow();
 });
+
+test("per-field fills take the value Jev chose for that field", () => {
+	const actions = candidates(
+		{
+			url: "https://example.test/checkout",
+			title: "Checkout",
+			snapshot:
+				'- textbox "Name" [ref=e1]: John Doe\n- textbox "City" [ref=e2]\n- button "Pay" [ref=e3]',
+		},
+		["John Doe", "New York"],
+		{ fieldValues: true },
+	);
+	expect(actions.filter((action) => action.kind === "fill")).toHaveLength(2);
+	const answers = {
+		next: {
+			type: "choice",
+			choice: "a0",
+			probabilities: { a0: 0.5, a1: 0.3, a2: 0.2 },
+		},
+		value_a0: { type: "choice", choice: "v0" },
+		value_a1: { type: "choice", choice: "v1" },
+	};
+	// Name already holds its chosen value, so the next most probable action runs.
+	const selected = select(actions, answers, ["John Doe", "New York"]);
+	expect(selected?.ref).toBe("e2");
+	expect(selected?.value).toBe("New York");
+	expect(actionCode(selected!)).toContain('"New York"');
+	expect(
+		select(
+			actions,
+			{ ...answers, next: { ...answers.next, choice: "missing" } },
+			[],
+		),
+	).toBeUndefined();
+});
+
+test("without per-field values the chosen action runs unchanged", () => {
+	const actions = candidates(
+		{
+			url: "https://example.test",
+			title: "",
+			snapshot: '- button "Go" [ref=e1]',
+		},
+		[],
+	);
+	expect(
+		select(
+			actions,
+			{ next: { type: "choice", choice: "wait", probabilities: { a0: 0.9 } } },
+			[],
+		)?.kind,
+	).toBe("wait");
+});