Remove some unnecessary string allocations in hosting layer

[elinor-fung]

• Make utils for ends_with and starts_with stop requiring a string
• Avoid creating a string for tracing when tracing is not enabled

This removes ~2000 transient string allocations in starting a console app.

[ghost]

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Issue Details

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• Make utils for ends_with and starts_with stop requiring a string
• Avoid creating a string for tracing when tracing is not enabled

This removes ~2000 transient string allocations in starting a console app.

Author:	elinor-fung
Assignees:	-
Labels:	area-Host
Milestone:	-

[vitek-karas]

Nice! Thanks a lot!