Clang format for east-const, and only format diffed files

[rboston628]

Description of work

Summary of work

Added the east-const option to the clang-format, and set pre-commit to only run on touched files.

To test:

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[github-actions]

👋 Hi, @rboston628,

Conflicts have been detected against the base branch. Please rebase your branch against the base branch.