feat(gdu): add bundle analyser for Vite builds

[amir-zahedi]

Summary

• Adds rollup-plugin-visualizer support for Vite builds when ANALYZE=true / gdu build -a
• Outputs bundle-report.html (interactive treemap) to the build output directory, matching existing webpack behaviour
• Uses try/catch dynamic import pattern (consistent with vanilla-extract plugin) — consumers need rollup-plugin-visualizer installed

Test plan

• yarn workspace gdu build exits 0
• ANALYZE=true APP_ENV=prod gdu build on a Vite MFE (fmo-booking) generates bundle-report.html (2.5 MB interactive treemap)
• Build without the flag produces no report
• Missing rollup-plugin-visualizer logs a warning instead of crashing

AG-17604

[Copilot]

Pull request overview

Adds an optional bundle analysis report for Vite-based SPA builds in gdu, gated behind the existing ANALYZE=true / gdu build -a flag, aiming to match the current webpack bundle-report.html behavior.

Changes:

• Conditionally adds rollup-plugin-visualizer to Vite build plugins when process.env.ANALYZE === 'true'.
• Writes a bundle-report.html report file and warns (without crashing) if the visualizer dependency is missing.
• Adds a changeset to publish the feature as a minor bump for gdu.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
packages/gdu/commands/build/buildSPA-vite.ts	Adds conditional runtime plugin injection for rollup-plugin-visualizer during Vite builds.
.changeset/vite-bundle-analyser.md	Declares a minor version bump for gdu documenting the new analyze behavior for Vite builds.

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[Copilot]

In production multi-env builds, Vite’s outDir is computed per config (e.g. ${guruConfig.outputPath}/${buildEnv}), but the visualizer report is always written to join(guruConfig.outputPath, 'bundle-report.html'). Since buildSPAVite loops over multiple configs, this will overwrite the same report file and place it outside the per-env output directory. Consider constructing the report filename from the current config’s build.outDir (or otherwise making it env-specific) and adding the visualizer plugin per-config inside the loop.

[Copilot]

The catch here will also handle cases where rollup-plugin-visualizer is installed but fails to load/execute for another reason (e.g. incompatible version, runtime error), yet the warning message specifically claims it is "not installed". Capture the error and either (a) tailor the message based on a module-not-found check, or (b) include the error details in the warning so failures aren’t misdiagnosed.

Suggested change

	} catch {
	console.warn(
	magenta(
	'Warning: rollup-plugin-visualizer is not installed. ' +
	'Install it to enable bundle analysis for Vite builds: ' +
	'yarn add -D rollup-plugin-visualizer',
	),
	);
	} catch (error) {
	const err = error as { code?: unknown; message?: unknown };
	const errorCode = typeof err.code === 'string' ? err.code : undefined;
	const isModuleNotFound =
	errorCode === 'MODULE_NOT_FOUND' ||
	errorCode === 'ERR_MODULE_NOT_FOUND';
	if (isModuleNotFound) {
	console.warn(
	magenta(
	'Warning: rollup-plugin-visualizer is not installed. ' +
	'Install it to enable bundle analysis for Vite builds: ' +
	'yarn add -D rollup-plugin-visualizer',
	),
	);
	} else {
	const errorMessage =
	typeof err.message === 'string'
	? err.message
	: String(error);
	console.warn(
	magenta(
	'Warning: Failed to load rollup-plugin-visualizer for bundle analysis. ' +
	`Error: ${errorMessage}`,
	),
	);
	}