docs(contributing): update setup instructions for pre-commit

Update CONTRIBUTING guide to reflect migration from custom git hooks to
standard pre-commit framework:

* Add pre-commit package to installation commands for Fedora and Windows
* Replace 'make githooks' with standard 'pre-commit install' command

This completes the migration to pre-commit started in previous refactor
commit, ensuring documentation matches current development workflow.

CONTRIBUTING.adoc

@@ -35,14 +35,14 @@ The preferred way to communicate is probably via Discord or GitHub issues.
 ```
 # Step1: setup compile env
 # - Fedora
-dnf install git go protobuf-compiler make -y
+dnf install git go protobuf-compiler make pre-commit -y
 # - Windows with chocolatey
-choco install git go protoc make python nodejs-lts -y
+choco install git go protoc make python nodejs-lts -y && pip install pre-commit
 
 # Step2: clone and setup repo
 git clone https://github.com/OliveTin/OliveTin.git
 cd OliveTin
-make githooks
+pre-commit install
 
 # Step3: compile binary for current dev env (OS, ARCH)
 # `make proto` will also run `make go-tools`, which installs "buf". This binary