Replace JuliaFormatter with Runic.jl in style guide

[ChrisRackauckas-Claude]

Summary

• Replace all JuliaFormatter references with Runic.jl documentation
• Update style rules to reflect Runic.jl's fixed formatting conventions
• Add notes throughout the guide about automatic enforcement by Runic.jl

Changes Made

Table of Contents

• Updated link from JuliaFormatter to Runic

High Level Rules Section

• Added notes that 4-space indentation is automatically enforced by Runic.jl
• Noted that line length limit must be managed manually (Runic doesn't wrap lines)

Whitespace Section

• Added introductory note that whitespace rules are automatically enforced by Runic.jl

Binary Operators Section

• Clarified that spaces ARE used around = in keyword arguments
• Changed "may be excluded" language to explicit "Exceptions (no spaces)" list
• Added type annotations (::) to the exceptions list

NamedTuples Section

• Updated to note that Runic.jl automatically formats named tuples

For Loops Section

• Added note that Runic.jl automatically converts = and ∈ to in

Replaced JuliaFormatter Section

The new Runic section includes:

• Description of Runic's zero-configuration philosophy
• Installation instructions
• Command-line usage examples
• Complete CI workflow YAML example
• Instructions for selectively disabling formatting (# runic: off/on)
• Note about JuliaFormatter comment compatibility (#! format: off/on)

Test plan

• Verify the FormatCheck.yml workflow in the repo already uses Runic (it does)
• Review that documentation accurately reflects Runic.jl behavior
• Verify all internal links in Table of Contents work correctly

🤖 Generated with Claude Code