Optimize mp-server dockerfile size

[kasper573]

The current image size is 1.5GB, but alpine + node 22 should only equal ~250mb, and at the time of writing this issue our bundled source code amounts to ~3MB, so 1.5GB is really bad.

Ideally produce a standalone js bundle that only requires node to run.

This is possible and I used to do this in this project with esbuild, but after introducing opentelemetry we can no longer use esbuild due to its node module monkeypatching system. This might be solved some day via open-telemetry/opentelemetry-js#4174.

Find a way!

[kasper573]

I tried using https://github.com/DrewCorlin/opentelemetry-esbuild-plugin-node and it didn't work. The plugin seemed to embed the correct runtime code (I inspected the generated js bundle) and the log outputs from otel seemed to be saying that instrumentation was enabled, but I didn't receive any telemetry in tempo. Not sure if this means that the plugin simply doesn't work or if I just messed up. Giving up on the plugin for now.