Fix bash tool visual line truncation

Use visual line counting (accounting for line wrapping) instead of logical
line counting for bash tool output in collapsed mode. Now consistent with
bash-execution.ts behavior.

- Add shared truncateToVisualLines utility
- Update tool-execution.ts to use Box for bash with visual truncation
- Update bash-execution.ts to use shared utility
- Pass TUI to ToolExecutionComponent for terminal width access

Fixes #275

packages/coding-agent/src/modes/interactive/components/visual-truncate.ts

@@ -0,0 +1,50 @@
+/**
+ * Shared utility for truncating text to visual lines (accounting for line wrapping).
+ * Used by both tool-execution.ts and bash-execution.ts for consistent behavior.
+ */
+
+import { Text } from "@mariozechner/pi-tui";
+
+export interface VisualTruncateResult {
+	/** The visual lines to display */
+	visualLines: string[];
+	/** Number of visual lines that were skipped (hidden) */
+	skippedCount: number;
+}
+
+/**
+ * Truncate text to a maximum number of visual lines (from the end).
+ * This accounts for line wrapping based on terminal width.
+ *
+ * @param text - The text content (may contain newlines)
+ * @param maxVisualLines - Maximum number of visual lines to show
+ * @param width - Terminal/render width
+ * @param paddingX - Horizontal padding for Text component (default 0).
+ *                   Use 0 when result will be placed in a Box (Box adds its own padding).
+ *                   Use 1 when result will be placed in a plain Container.
+ * @returns The truncated visual lines and count of skipped lines
+ */
+export function truncateToVisualLines(
+	text: string,
+	maxVisualLines: number,
+	width: number,
+	paddingX: number = 0,
+): VisualTruncateResult {
+	if (!text) {
+		return { visualLines: [], skippedCount: 0 };
+	}
+
+	// Create a temporary Text component to render and get visual lines
+	const tempText = new Text(text, paddingX, 0);
+	const allVisualLines = tempText.render(width);
+
+	if (allVisualLines.length <= maxVisualLines) {
+		return { visualLines: allVisualLines, skippedCount: 0 };
+	}
+
+	// Take the last N visual lines
+	const truncatedLines = allVisualLines.slice(-maxVisualLines);
+	const skippedCount = allVisualLines.length - maxVisualLines;
+
+	return { visualLines: truncatedLines, skippedCount };
+}