Fix spelling and grammar errors in comments

[brandbarr]

Summary

This PR corrects several spelling and grammar errors found in code comments across the fflib-apex-common library to
improve documentation clarity and professionalism.

Changes Made

• fflib_Application.cls
  • Fixed "Map ofi interfaces" → "Map of interfaces" (line 142)
  • Fixed "Consturcts" → "Constructs" (line 192)
  • Fixed @Param → @param for proper JavaDoc formatting (line 196)
  • Fixed "then" → "than" in comparison context (lines 89, 105)
• fflib_ISObjectUnitOfWork.cls
  • Fixed "Register a generic peace of work" → "Register a generic piece of work" (line 218)
• fflib_StringBuilder.cls
  • Fixed "where developed" → "were developed" (line 30)

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This change is 

[daveespo]

Thank you!

@daveespo reviewed 3 of 3 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @brandbarr)

[ImJohnMDaniel]

@brandbarr -- thanks for the updates. Cheers!