feat(plugin): make esbuild resolution resilient to package managers

[ByteYue]

Description

Replaces the hardcoded node_modules/.bin/esbuild lookup with a robust multi-stage resolution strategy.

• Adds resolveEsbuildBin() with 3 fallbacks
• Stage 1: Leverages import.meta.resolve to parse the actually installed esbuild/package.json and find its declared bin file.
• Stage 2: Falls back to the raw node_modules/.bin path.
• Stage 3: Falls back to the global PATH via which esbuild.
• Updates transpilePluginTs() to use this new helper.

This prevents silent transpilePluginTs failures on developer machines or custom environments where package managers like pnpm hoist bins differently.

[jackwener]

Deep review completed. I kept the esbuild resolution fallback idea, rebased it onto current plugin infrastructure, and kept the patch focused on the actual resilience fix plus targeted coverage.