Documentation refactor

[Davidyz]

Refactor the documentation for clarity:

• separate API references and include integration guide for the neovim plugin;
• include brief introductions on the jobrunner API.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.77%. Comparing base (7593cc5) to head (88ad634).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #248   +/-   ##
=======================================
  Coverage   99.77%   99.77%           
=======================================
  Files          24       24           
  Lines        1762     1762           
=======================================
  Hits         1758     1758           
  Misses          4        4           

☔ 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.