Enable offline functionality for frontend

[saichander17]

Summary

This PR removes functionality which downloads fonts/css files from internet and puts them available in the local build itself. The UI seems to call other domains as well but they don't block the UI until timeout occurs and hence it's not causing any functionality issues.

Problems this PR solves in airgapped environments

1. Long waiting time to load UI as it waits for fonts and css file requests to timeout
2. Broken charts due to uPlot.min.css file not being available
3. Incorrect fonts being shown as fonts couldn't be downloaded

Related Issues / PR's

Fix for: #5036

External domains still being called from the frontend

These domains still get called from the UI but they don't block the UI until timeout or anything as per my testing.

1. https://analytics-cdn.signoz.io/
2. https://widget.intercom.io/
3. https://api.github.com/repos/signoz/signoz/releases/latest
4. https://js.intercomcdn.com/

Known problems

1. Monaco editor doesn't load to import JSON (load monaco from node_modules suren-atoyan/monaco-react#12). I'm not sure if I should follow the steps mentioned in this issue or is there any problem with the approach.

Clarifications needed

• I've placed uPlot.min.css under public/css and imported in the index html. Should I do it this way or import it in the src/styles.scss similar to how it's done for periscope.scss?

My suggestion would be to go ahead and merge the PR as it at least solves the biggest issues in airgapped environments right now and take other updates periodically.

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Important

Enable offline functionality by localizing fonts and CSS in the frontend, addressing airgapped environment issues.

• Behavior:
  • Removes external font and CSS file requests in index.html.ejs, replacing them with local paths.
  • Adds uPlot.min.css to public/css and updates index.html.ejs to use it locally.
• Styles:
  • Adds @font-face declarations in styles.scss for Inter, Work Sans, Space Mono, and Fira Code fonts, sourcing them from local files.
• Misc:
  • Updates image paths in index.html.ejs to use local images instead of external URLs.

^{This description was created by for 2a1e8da. It will automatically update as commits are pushed.}

[welcome]

Welcome to the SigNoz community! Thank you for your first pull request and making this project better. 🤗

[CLAassistant]

All committers have signed the CLA.

[ellipsis-dev]

❌ Changes requested. Reviewed everything up to 2a1e8da in 27 seconds

More details

• Looked at 90 lines of code in 3 files
• Skipped 5 files when reviewing.
• Skipped posting 2 drafted comments based on config settings.

1. frontend/src/index.html.ejs:55

• Draft comment:
  The external font links have been removed, but the HTML does not reference the locally defined fonts. Ensure that the HTML or CSS uses the locally defined fonts from styles.scss.
• Reason this comment was not posted:
  Comment did not seem useful.

2. frontend/src/styles.scss:277

• Draft comment:
  Avoid hardcoding color values like rgb(136, 136, 136). Use design tokens or predefined color constants instead. This applies to other color values in this file as well.
• Reason this comment was not posted:
  Marked as duplicate.

Workflow ID: wflow_9obqgpOwqsvQ2Ek3

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[vikrantgupta25]

the changes look good, can you attach a video recording with launching query service locally / frontend locally and turn off the internet access. Load certain dashboards and check if things are looking fine ?

[vikrantgupta25]

LGTM

[welcome]

Congrats on merging your first pull request!

We here at SigNoz are proud of you! 🥳

[prashant-shahi]

@saichander17 Can you please sign the CLA? https://cla-assistant.io/SigNoz/signoz?pullRequest=6152