Update to documentation and tests

[StuartWheater]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 29.67%. Comparing base (15dd8c4) to head (b288a3a).
⚠️ Report is 4 commits behind head on v6.3.6-dev.

Additional details and impacted files

@@             Coverage Diff             @@
##           v6.3.6-dev     #491   +/-   ##
===========================================
  Coverage       29.67%   29.67%           
===========================================
  Files             140      140           
  Lines            5806     5806           
===========================================
  Hits             1723     1723           
  Misses           4083     4083           

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[timcadman]

Looks good. Main changes appear to be:

1. pkgdown docs rebuilt to Bootstrap 5
2. Tests updated for testthat 3 — context calls commented out
3. DESCRIPTION — min R bumped 4.0.0 → 4.1.0; testthat pinned >= 3.0.0.
4. README — install example version bumped 6.3.4 → 6.3.6.