Show 404 page for non-existent routes

[ryan-pratt]

closes #1775

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.59%. Comparing base (620b543) to head (e47db67).
Report is 10 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1789      +/-   ##
==========================================
+ Coverage   79.56%   79.59%   +0.02%     
==========================================
  Files         517      517              
  Lines       40737    40737              
==========================================
+ Hits        32414    32423       +9     
+ Misses       8323     8314       -9     

Flag	Coverage Δ
python	84.32% <ø> (+0.06%)	⬆️
ruby-api	48.64% <ø> (ø)
ruby-backend	82.61% <ø> (ø)

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[jmthomas]

Going to bad urls like http://localhost:2900/tools/jason now results in:

[jmthomas]

Looks awesome!