chore: update README.md & development instructions

[jonas-jonas]

Related Issue or Design Document

Checklist

• I have read the contributing guidelines and signed the CLA.
• I have referenced an issue containing the design document if my change introduces a new feature.
• I have read the security policy.
• I confirm that this pull request does not address a security vulnerability.
  If this pull request addresses a security vulnerability,
  I confirm that I got approval (please contact [email protected]) from the maintainers to push the changes.
• I have added tests that prove my fix is effective or that my feature works.
• I have added the necessary documentation within the code base (if appropriate).

Further comments

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 42.44%. Comparing base (f3fad4d) to head (afd41e8).
Report is 19 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #256      +/-   ##
==========================================
+ Coverage   42.43%   42.44%   +0.01%     
==========================================
  Files         136      138       +2     
  Lines        2008     2092      +84     
  Branches      288      310      +22     
==========================================
+ Hits          852      888      +36     
- Misses       1149     1192      +43     
- Partials        7       12       +5     

Components	Coverage Δ
@ory/elements-react	37.25% <36.73%> (+0.46%)	⬆️
@ory/nextjs	64.33% <74.24%> (-1.65%)	⬇️