feat(ui): Phase 30 ship-class calculator with goal-seek and reach circles

Fuse the standalone ship-class designer (Phases 17/18) into a sidebar calculator: live mass/speed/attack/defence/bombing results, a planet build-rate readout, single-target goal-seek, a modernization-cost mode, and auto reach circles on the map for the selected planet.

pkg/calc becomes the single source for the new math (no mirroring): extract BombingPower from the engine model and the per-turn ship-production loop from controller.ProduceShip into pkg/calc (engine now delegates), and add inverse goal-seek solvers in pkg/calc/solve.go. Thin-bridge the combat, planet-build, and solver functions through ui/core/calc + ui/wasm and rebuild core.wasm.

Remove the standalone designer view/route; the ship-classes table and the view/bottom menus open the calculator via a shared request store.

Docs: rewrite ui/PLAN.md Phase 30, adjust Phase 34 (realistic forecast + CAP/COL ownership), add ui/docs/calculator-ux.md, extend calc-bridge.md, fix navigation.md; remove ui/CALCULATOR.md.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

ui/frontend/tests/reach-circles.test.ts

@@ -0,0 +1,55 @@
+import { describe, expect, test } from "vitest";
+
+import {
+	computeReachCircles,
+	reachBound,
+	REACH_CIRCLE_ID_PREFIX,
+} from "../src/map/reach-circles";
+
+const CENTER = { x: 500, y: 500 };
+
+describe("computeReachCircles", () => {
+	test("no circles for a non-positive speed", () => {
+		expect(computeReachCircles(CENTER, 0, 1000, 1000, "torus")).toEqual([]);
+		expect(computeReachCircles(CENTER, -5, 1000, 1000, "torus")).toEqual([]);
+	});
+
+	test("torus: a slow ship shows all three rings", () => {
+		// bound = min(1000,1000)/2 = 500; speed 100 keeps every ring inside.
+		const circles = computeReachCircles(CENTER, 100, 1000, 1000, "torus");
+		expect(circles.map((c) => c.radius)).toEqual([100, 200, 300]);
+		expect(circles[0].id).toBe(REACH_CIRCLE_ID_PREFIX + 1);
+		expect(circles[0].style.strokeColor).toBeDefined();
+	});
+
+	test("torus: a ship reaching the wrap midpoint shows one ring", () => {
+		// speed 500 hits the bound on turn 1, so turn 2 is dropped.
+		const circles = computeReachCircles(CENTER, 500, 1000, 1000, "torus");
+		expect(circles).toHaveLength(1);
+		expect(circles[0].radius).toBe(500);
+	});
+
+	test("torus: a mid-speed ship shows two rings", () => {
+		// speed 300: ring 1 = 300 (< 500), ring 2 = 600; ring 3 dropped
+		// because 2 × 300 = 600 ≥ 500.
+		const circles = computeReachCircles(CENTER, 300, 1000, 1000, "torus");
+		expect(circles.map((c) => c.radius)).toEqual([300, 600]);
+	});
+
+	test("no-wrap: the bound is the farthest corner", () => {
+		// origin at a corner → farthest corner is the diagonal.
+		expect(reachBound({ x: 0, y: 0 }, 1000, 1000, "no-wrap")).toBeCloseTo(
+			Math.hypot(1000, 1000),
+			6,
+		);
+		const circles = computeReachCircles(
+			{ x: 0, y: 0 },
+			500,
+			1000,
+			1000,
+			"no-wrap",
+		);
+		// bound ≈ 1414, so all three rings fit.
+		expect(circles.map((c) => c.radius)).toEqual([500, 1000, 1500]);
+	});
+});