fix(webapp): position annotation context menu

[eh-am]

Closes #1533

[codecov]

Codecov Report

Base: 66.40% // Head: 66.40% // No change to project coverage 👍

Coverage data is based on head (2e14fa3) compared to base (740a0f7).
Patch has no changes to coverable lines.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1534   +/-   ##
=======================================
  Coverage   66.40%   66.40%           
=======================================
  Files         147      147           
  Lines        4997     4997           
  Branches     1356     1356           
=======================================
  Hits         3318     3318           
  Misses       1674     1674           
  Partials        5        5           

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[github-actions]

size-limit report 📦

Path	Size	Loading time (3g)	Running time (snapdragon)	Total time
webapp/public/assets/app.js	443.54 KB (+0.02% 🔺)	8.9 s (+0.02% 🔺)	3.4 s (+7.85% 🔺)	12.3 s
webapp/public/assets/app.css	17.02 KB (0%)	341 ms (0%)	0 ms (+100% 🔺)	341 ms
webapp/public/assets/styles.css	9.49 KB (0%)	190 ms (0%)	0 ms (+100% 🔺)	190 ms
packages/pyroscope-flamegraph/dist/index.js	92.09 KB (0%)	1.9 s (0%)	1.3 s (-15.51% 🔽)	3.2 s
packages/pyroscope-flamegraph/dist/index.node.js	91.98 KB (0%)	1.9 s (0%)	557 ms (-17.27% 🔽)	2.4 s
packages/pyroscope-flamegraph/dist/index.css	7.32 KB (0%)	147 ms (0%)	0 ms (+100% 🔺)	147 ms

[Rperry2174]

LGTM -- added one comment about threshold variable