streamer: Resolve Rust 1.88 clippy lints and format strings

[steviez]

Problem

Working towards #6850, broken out from #6854

Summary of Changes

• Run cargo clippy --fix --tests with Rust 1.88.0 set in rust-toolchain.toml
  • These should only be instances of uninlined_format_args
• Run cargo fmt with format_strings = true set in rustfmt.toml

[codecov-commenter]

Codecov Report

❌ Patch coverage is 60.60606% with 13 lines in your changes missing coverage. Please review.
✅ Project coverage is 83.2%. Comparing base (09fe49b) to head (5635a04).
⚠️ Report is 2874 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #7001   +/-   ##
=======================================
  Coverage    83.2%    83.2%           
=======================================
  Files         853      853           
  Lines      375393   375395    +2     
=======================================
+ Hits       312474   312485   +11     
+ Misses      62919    62910    -9     

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