fix ProjectRoot injection, panic if injection failed

[cpunion]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 7.69231% with 24 lines in your changes missing coverage. Please review.

Project coverage is 54.54%. Comparing base (989ce2f) to head (d3c2025).
Report is 7 commits behind head on main.

Files with missing lines	Patch %	Lines
cmd/internal/rungo/run.go	0.00%	15 Missing ⚠️
inject.go	10.00%	8 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #29      +/-   ##
==========================================
+ Coverage   54.11%   54.54%   +0.43%     
==========================================
  Files          40       40              
  Lines        2761     2737      -24     
==========================================
- Hits         1494     1493       -1     
+ Misses       1208     1184      -24     
- Partials       59       60       +1     

Flag	Coverage Δ
unittests	54.54% <7.69%> (+0.43%)	⬆️

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