fix(coding-agent): configure inline tool image width

closes #3508

packages/coding-agent/src/core/settings-manager.ts

@@ -25,6 +25,7 @@ export interface RetrySettings {
 
 export interface TerminalSettings {
 	showImages?: boolean; // default: true (only relevant if terminal supports images)
+	imageWidthCells?: number; // default: 60 (preferred inline image width in terminal cells)
 	clearOnShrink?: boolean; // default: false (clear empty rows when content shrinks)
 }
 
@@ -870,6 +871,23 @@ export class SettingsManager {
 		this.save();
 	}
 
+	getImageWidthCells(): number {
+		const width = this.settings.terminal?.imageWidthCells;
+		if (typeof width !== "number" || !Number.isFinite(width)) {
+			return 60;
+		}
+		return Math.max(1, Math.floor(width));
+	}
+
+	setImageWidthCells(width: number): void {
+		if (!this.globalSettings.terminal) {
+			this.globalSettings.terminal = {};
+		}
+		this.globalSettings.terminal.imageWidthCells = Math.max(1, Math.floor(width));
+		this.markModified("terminal", "imageWidthCells");
+		this.save();
+	}
+
 	getClearOnShrink(): boolean {
 		// Settings takes precedence, then env var, then default false
 		if (this.settings.terminal?.clearOnShrink !== undefined) {