chore: import upstream snapshot with attribution

tools/ui/scripts/vite-plugin-build-info.ts

@@ -0,0 +1,41 @@
+import { writeFileSync, existsSync } from 'node:fs';
+import { resolve } from 'path';
+import type { Plugin } from 'vite';
+import { BUILD_CONFIG } from '../src/lib/constants/pwa';
+
+let processed = false;
+
+const OUTPUT_DIR = process.env.LLAMA_UI_OUT_DIR ?? BUILD_CONFIG.OUTPUT_DIR;
+
+/**
+ * Write build.json with the llama.cpp release build number.
+ *
+ * LLAMA_BUILD_NUMBER is passed from CMake -> npm -> vite via env var.
+ * Used for display of the current llama-server release (e.g. "b1234").
+ */
+export function buildInfoPlugin(): Plugin {
+	return {
+		name: 'llamacpp:build-info',
+		apply: 'build',
+		closeBundle() {
+			setTimeout(() => {
+				try {
+					if (processed) return;
+					processed = true;
+
+					const buildNumber = process.env.LLAMA_BUILD_NUMBER || 'b0000';
+
+					const outDir = resolve(OUTPUT_DIR);
+					const indexPath = resolve(outDir, 'index.html');
+					if (!existsSync(indexPath)) return;
+
+					const buildJsonPath = resolve(outDir, 'build.json');
+					writeFileSync(buildJsonPath, JSON.stringify({ version: buildNumber }), 'utf-8');
+					console.log(`Created build.json (version: ${buildNumber})`);
+				} catch (error) {
+					console.error('Failed to write build.json:', error);
+				}
+			}, 100);
+		}
+	};
+}