Switch to esbuild's native watcher for building extensions

[mjbvz]

This should be good to use now and also lets us benefit from incremental builds. In my testing the memory and cpu usage seems reasonable but will keep an eye on this

[Copilot]

Pull request overview

Switches the extension/webview esbuild build scripts from @parcel/watcher-driven rebuilds to esbuild’s native context(...).watch() to enable incremental builds and simplify watch mode.

Changes:

• Move default webview esbuild options into run() and make build() directly call esbuild.build(options).
• Replace @parcel/watcher-based --watch implementation with esbuild.context(...).watch() in both common scripts.
• Replace tryBuild error-swallowing flow with an esbuild plugin that invokes didBuild on build end.

Show a summary per file

File	Description
extensions/esbuild-webview-common.mts	Uses esbuild’s native watch mode for webview builds and wires didBuild via an onEnd plugin.
extensions/esbuild-extension-common.mts	Uses esbuild’s native watch mode for extension builds and wires didBuild via an onEnd plugin.

Copilot's findings

Comments suppressed due to low confidence (2)

extensions/esbuild-webview-common.mts:67

• Switching to ctx.watch() means rebuilds (and therefore didBuild) will only run when esbuild detects an input/dependency change. If callers use didBuild to copy non-imported assets from config.srcDir (e.g. shell scripts, JSON, etc.), edits to those files will no longer trigger the post-build step. Consider adding a lightweight directory watcher for config.srcDir (or documenting the limitation) so non-bundled files still get picked up during --watch.

		const ctx = await esbuild.context(resolvedOptions);
		await ctx.watch();

extensions/esbuild-extension-common.mts:87

• Switching to ctx.watch() means rebuilds (and therefore didBuild) will only run when esbuild detects an input/dependency change. Some callers use didBuild to copy non-imported assets from config.srcDir (e.g. extensions/git copies *.sh files); edits to those files will no longer trigger during --watch. Consider adding a directory watcher for config.srcDir (or otherwise triggering didBuild/ctx.rebuild() on non-bundled file changes).

		const ctx = await esbuild.context(resolvedOptions);
		await ctx.watch();

• Files reviewed: 2/2 changed files
• Comments generated: 4