Fix TUI rendering with wrong dimensions after suspend/resume

- Send SIGWINCH to self on terminal start to refresh stale dimensions (Unix only)
- Change requestRender(true) to set previousWidth = -1 to trigger widthChanged
- Update first render condition to skip when widthChanged is true

Fixes #599

packages/tui/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- TUI renders with wrong dimensions after suspend/resume if terminal was resized while suspended ([#599](https://github.com/badlogic/pi-mono/issues/599))
+
 ## [0.42.4] - 2026-01-10
 
 ## [0.42.3] - 2026-01-10

packages/tui/src/terminal.ts

@@ -70,6 +70,12 @@ export class ProcessTerminal implements Terminal {
 		// Set up resize handler immediately
 		process.stdout.on("resize", this.resizeHandler);
 
+		// Refresh terminal dimensions - they may be stale after suspend/resume
+		// (SIGWINCH is lost while process is stopped). Unix only.
+		if (process.platform !== "win32") {
+			process.kill(process.pid, "SIGWINCH");
+		}
+
 		// Query and enable Kitty keyboard protocol
 		// The query handler intercepts input temporarily, then installs the user's handler
 		// See: https://sw.kovidgoyal.net/kitty/keyboard-protocol/

packages/tui/src/tui.ts

@@ -164,7 +164,7 @@ export class TUI extends Container {
 	requestRender(force = false): void {
 		if (force) {
 			this.previousLines = [];
-			this.previousWidth = 0;
+			this.previousWidth = -1; // -1 triggers widthChanged, forcing a full clear
 			this.cursorRow = 0;
 		}
 		if (this.renderRequested) return;
@@ -334,8 +334,8 @@ export class TUI extends Container {
 		// Width changed - need full re-render
 		const widthChanged = this.previousWidth !== 0 && this.previousWidth !== width;
 
-		// First render - just output everything without clearing
-		if (this.previousLines.length === 0) {
+		// First render - just output everything without clearing (assumes clean screen)
+		if (this.previousLines.length === 0 && !widthChanged) {
 			let buffer = "\x1b[?2026h"; // Begin synchronized output
 			for (let i = 0; i < newLines.length; i++) {
 				if (i > 0) buffer += "\r\n";