Update logo, favicon, and overview images

[niksirbi]

Description

What is this PR

• Bug fix
• Addition of a new feature
• Other: Docs website

Why is this PR needed?

Updates to the designs of the logo and favicon, following discussions on Zulip.

What does this PR do?

• The text in the logo is now italicised
• The favicon now contains a small italicised "m" in its centre
• The "overview" image (displayed in README and homepage) is updated to incorporate the logo

This is how the website header will show up henceforth:

References

Follows up #614
See "#Movement > logo ideas" on Zulip.

How has this PR been tested?

Local docs build.

Is this a breaking change?

No.

Does this PR require an update to the documentation?

It is in itself an update of docs.

Checklist:

• The code has been tested locally
• Tests have been added to cover all new functionality
• The documentation has been updated to reflect any changes
• The code has been formatted with pre-commit

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (8f38215) to head (919dc50).

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #632   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           32        32           
  Lines         1859      1859           
=========================================
  Hits          1859      1859           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[lochhh]

🚀

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud