chore: drop non-code junk (pi-mono-reference, runtime state, root duplicates)

Remove files that should never have been tracked:

- pi-mono-reference/: 688-file copy of an upstream monorepo, zero imports,
  used only as offline human reference
- build/electron-builder.runtime.json: environment-specific build artifact
  with hardcoded local paths
- state/cancel-signal-state.json: runtime state written by the app
- prompt.txt, logo.svg (root): exact duplicates of the canonical copies
  under .planning/archive/ and assets/

Add state/ to .gitignore so future runtime state stays out.

pi-mono-reference/packages/coding-agent/test/bash-execution-width.test.ts

@@ -1,80 +0,0 @@
-/**
- * Test that BashExecutionComponent's collapsed output respects the render-time width,
- * not a stale captured width. Regression test for #2569.
- */
-import { visibleWidth } from "@mariozechner/pi-tui";
-import { beforeAll, describe, expect, it } from "vitest";
-import { BashExecutionComponent } from "../src/modes/interactive/components/bash-execution.js";
-import { initTheme } from "../src/modes/interactive/theme/theme.js";
-
-/** Minimal TUI stub that only exposes terminal.columns */
-function createTuiStub(columns: number): { columns: number; stub: any } {
-	const state = { columns };
-	const stub = {
-		terminal: {
-			get columns() {
-				return state.columns;
-			},
-			get rows() {
-				return 24;
-			},
-		},
-		// Loader calls ui.addInterval / ui.removeInterval
-		addInterval: (_cb: () => void, _ms: number) => ({ dispose: () => {} }),
-		removeInterval: () => {},
-		requestRender: () => {},
-	};
-	return { columns: state.columns, stub };
-}
-
-describe("BashExecutionComponent width handling (#2569)", () => {
-	beforeAll(() => {
-		initTheme(undefined, false);
-	});
-
-	it("collapsed preview lines respect render-time width, not construction-time width", () => {
-		const wideWidth = 200;
-		const narrowWidth = 80;
-
-		const { stub } = createTuiStub(wideWidth);
-		const component = new BashExecutionComponent("pwd", stub);
-
-		// Add output with long lines that will wrap differently at different widths
-		const longLine = "x".repeat(150);
-		component.appendOutput(`${longLine}\n${longLine}\n`);
-
-		// Complete the command so it enters collapsed mode
-		component.setComplete(0, false);
-
-		// Render at the narrow width (simulating a resize or split pane)
-		const lines = component.render(narrowWidth);
-
-		// Every rendered line must fit within the narrow width
-		for (let i = 0; i < lines.length; i++) {
-			const w = visibleWidth(lines[i]);
-			expect(w, `Line ${i} visibleWidth=${w} > ${narrowWidth}`).toBeLessThanOrEqual(narrowWidth);
-		}
-	});
-
-	it("re-computes lines when width changes between renders", () => {
-		const { stub } = createTuiStub(200);
-		const component = new BashExecutionComponent("echo hello", stub);
-
-		const longLine = "abcdefghij".repeat(20); // 200 chars
-		component.appendOutput(`${longLine}\n`);
-		component.setComplete(0, false);
-
-		// First render at width 200
-		const lines200 = component.render(200);
-		for (const line of lines200) {
-			expect(visibleWidth(line)).toBeLessThanOrEqual(200);
-		}
-
-		// Second render at width 60 (split pane scenario)
-		const lines60 = component.render(60);
-		for (let i = 0; i < lines60.length; i++) {
-			const w = visibleWidth(lines60[i]);
-			expect(w, `Line ${i} visibleWidth=${w} > 60`).toBeLessThanOrEqual(60);
-		}
-	});
-});