ui/phase-22: skip the no-op stance click in the races table

Clicking the already-active WAR/PEACE button still appended a
\`setDiplomaticStance\` whose \`relation\` matched the row's current
value. The engine would accept the duplicate harmlessly, but the
order tab inflates with rows that say nothing and every auto-sync
re-ships the redundant payload. Compare against the overlayed
stance (so a queued-but-not-applied change suppresses a re-click
that matches the *intended* state, not just the server snapshot)
and short-circuit when they agree. Mirrors the vote picker, which
already had the same guard.

vitest.config.ts: \`mergeConfig\` refuses callback-form base
configs, so resolve \`vite.config.ts\`'s callback with the test
context first and merge the plain object. Surfaced after the
\`loadEnv\` migration switched the root config to the callback
form.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ui/frontend/tests/table-races.test.ts

@@ -226,6 +226,18 @@ describe("races table", () => {
 		expect(names).toEqual(["Beta", "Gamma", "Alpha"]);
 	});
 
+	test("clicking the already-active stance is a no-op (no command queued)", async () => {
+		const ui = mountTable(
+			makeReport([race({ name: "Andori", relation: "WAR" })]),
+		);
+		await fireEvent.click(ui.getByTestId("races-stance-war"));
+		// Give the async handler one microtask to settle, then assert
+		// the draft remained empty — the click matched the current
+		// stance, so nothing should land in the order queue.
+		await Promise.resolve();
+		expect(draft.commands).toHaveLength(0);
+	});
+
 	test("clicking PEACE on a WAR row appends setDiplomaticStance and flips the overlay", async () => {
 		const ui = mountTable(
 			makeReport([race({ name: "Andori", relation: "WAR" })]),