Docs: Add Product Hunt info

[huynhicode]

📑 Summary

This PR contains updates to the Docs:

• update fourth card on homepage to include Product Hunt link
• update navbar Integrations link to route to Mermaid Chart page
• add Product Hunt badge to Mermaid Chart page
• update Announcements page to include Product Hunt info

Resolves #

📏 Design Decisions

Design decisions made by Mermaid Chart team.

📋 Tasks

Make sure you

• 📖 have read the contribution guidelines
• 💻 have added necessary unit/e2e tests.
• 📓 have added documentation. Make sure MERMAID_RELEASE_VERSION is used for all new features.
• 🔖 targeted develop branch

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[codecov]

Codecov Report

Merging #4900 (7b20e7e) into master (f1895ac) will decrease coverage by 32.37%.
Report is 188 commits behind head on master.
The diff coverage is 24.45%.

❗ Current head 7b20e7e differs from pull request most recent head dc04d17. Consider uploading reports for the commit dc04d17 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #4900       +/-   ##
===========================================
- Coverage   76.03%   43.67%   -32.37%     
===========================================
  Files         146       20      -126     
  Lines       14569     4632     -9937     
  Branches      592       21      -571     
===========================================
- Hits        11078     2023     -9055     
+ Misses       3368     2608      -760     
+ Partials      123        1      -122     

Flag	Coverage Δ
e2e	?
unit	43.67% <24.45%> (-1.89%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
packages/mermaid/src/config.ts	52.22% <100.00%> (-22.27%)	⬇️
packages/mermaid/src/diagrams/gantt/ganttDb.js	76.67% <100.00%> (-7.10%)	⬇️
packages/mermaid/src/diagrams/common/commonDb.ts	87.50% <87.50%> (ø)
packages/mermaid/src/diagrams/common/common.ts	52.78% <10.00%> (-25.05%)	⬇️
packages/mermaid/src/utils/sanitizeDirective.ts	13.09% <13.09%> (ø)
packages/mermaid/src/utils.ts	42.35% <22.96%> (-17.96%)	⬇️

... and 136 files with indirect coverage changes