fix: resolve expanding chars

[charlesrocket]

total capacity for Column and mandatory .chars.pop().

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 75.56%. Comparing base (a149fa5) to head (fc3904b).
Report is 2 commits behind head on trunk.

Additional details and impacted files

@@           Coverage Diff           @@
##            trunk       #8   +/-   ##
=======================================
  Coverage   75.56%   75.56%           
=======================================
  Files           1        1           
  Lines         176      176           
=======================================
  Hits          133      133           
  Misses         43       43           

Files with missing lines	Coverage Δ
src/main.zig	75.56% <100.00%> (ø)

[charlesrocket]

Memory usage is within the expected range now.