Add log-viewer-webui component with boilerplate Fastify server.

[kirkrodrigues]

Description

To integrate the log-viewer with the CLP package, we plan to add a new webapp that consists of a React frontend and a Fastify backend:

• The backend will host the log-viewer.
• The backend will also handle requests to decompress an IR file.
• The frontend will embed the log-viewer in an iframe.
• The frontend will also include controls for jumping between different pages/chunks of the IR file, and jumping between different splits of the log file.

We will integrate this new webapp with the package by embedding it in an iframe in the webui.

This convoluted implementation is for two reasons:

• Integrating the log-viewer with the current webui is non-trivial because the webui is written Meteor which doesn't have good support for web workers.
• The log-viewer isn't yet embeddable as a React component.

This PR starts a new component, log-viewer-webui, which contains this webapp. The webapp currently only contains a boilerplate Fastify app.

Note that we haven't yet added the new component to the linting workflow since that requires downloading a new node version which would make the PR a bit bigger.

Validation performed

• Validated npm lint:check passes
• Validated npm test passes.

[junhaoliao]

Looks good to me.

I verified all routes with Postman and also ensured all npm scripts added in package.json work, including the lint and test ones. The docs/srv/dev-guide md looks good but we do need to publish the site when we merge, or the docs.yscope.com link in components/log-viewer-webui/README.md won't work.

For the env files, we can create a .env.local file for entering debug config without git tracking it. That can be done in another PR, preferably after we enable the server in the CLP package / Taskfile.

I agree with the PR title as the squashed commit message.