Add MacOS installation instructions to README

[Copilot]

README only had Linux installation instructions. Added MacOS support for both Intel and Apple Silicon architectures.

Changes

• Added MacOS installation commands for darwin_amd64 (Intel) and darwin_arm64 (Apple Silicon)
• Updated Linux examples to use amd64/arm64 instead of 386
• All commands reference latest release v0.1.105

# For MacOS (Intel)
sudo curl --fail --location --output /usr/local/bin/kit https://github.com/kitproj/kit/releases/download/v0.1.105/kit_v0.1.105_darwin_amd64
sudo chmod +x /usr/local/bin/kit

# For MacOS (Apple Silicon)
sudo curl --fail --location --output /usr/local/bin/kit https://github.com/kitproj/kit/releases/download/v0.1.105/kit_v0.1.105_darwin_arm64
sudo chmod +x /usr/local/bin/kit

Original prompt

Make sure the README has instructions to install on both Linux and MacOS, and the version is the latest released version.

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