For tags header, fallback to params for the tag name

[acelaya]

Avoid a flickering of the tag name when loading visits for a tag, by falling back to the value from the route while the tag info is being loaded.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (main@f6979c1). Learn more about missing BASE report.
⚠️ Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
src/visits/TagVisitsHeader.tsx	0.00%	0 Missing and 2 partials ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #922   +/-   ##
=======================================
  Coverage        ?   84.74%           
=======================================
  Files           ?      187           
  Lines           ?     2831           
  Branches        ?      381           
=======================================
  Hits            ?     2399           
  Misses          ?      124           
  Partials        ?      308           

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