Switch from JuliaFormatter to Runic.jl for code formatting

- Update CI workflow to use fredrikekre/runic-action@v1
- Remove .JuliaFormatter.toml configuration
- Format all source files with Runic.jl

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: claude

.JuliaFormatter.toml

@@ -0,0 +1,19 @@
+name: format-check
+
+on:
+  push:
+    branches:
+      - 'master'
+      - 'main'
+      - 'release-'
+    tags: '*'
+  pull_request:
+
+jobs:
+  runic:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: fredrikekre/runic-action@v1
+        with:
+          version: '1'

.github/workflows/FormatCheck.yml

@@ -1,8 +1,10 @@
 using OrdinaryDiffEqOperatorSplitting
 using Documenter, DocumenterCitations
 
-DocMeta.setdocmeta!(OrdinaryDiffEqOperatorSplitting, :DocTestSetup,
-    :(using OrdinaryDiffEqOperatorSplitting); recursive = true)
+DocMeta.setdocmeta!(
+    OrdinaryDiffEqOperatorSplitting, :DocTestSetup,
+    :(using OrdinaryDiffEqOperatorSplitting); recursive = true
+)
 
 const is_ci = haskey(ENV, "GITHUB_ACTIONS")
 
@@ -16,7 +18,7 @@ makedocs(
     format = Documenter.HTML(
         assets = [
             "assets/citations.css",
-        # "assets/favicon.ico"
+            # "assets/favicon.ico"
         ],
         # canonical = "https://localhost/",
         collapselevel = 1
@@ -31,7 +33,7 @@ makedocs(
         "Theory Manual" => "topics/time-integration.md",
         "api-reference/index.md",
         "devdocs/index.md",
-        "references.md"
+        "references.md",
     ],
     plugins = [
         bibtex_plugin,
@@ -45,6 +47,6 @@ deploydocs(
     devbranch = "main",
     versions = [
         "stable" => "v^",
-        "dev" => "dev"
+        "dev" => "dev",
     ]
 )

docs/make.jl

@@ -5,7 +5,7 @@
 This type of function describes a set of connected inner functions in mass-matrix form, as usually found in operator splitting procedures.
 """
 struct GenericSplitFunction{fSetType <: Tuple, idxSetType <: Tuple, sSetType <: Tuple} <:
-       AbstractOperatorSplitFunction
+    AbstractOperatorSplitFunction
     # Tuple containing the atomic ode functions or further nested split functions.
     functions::fSetType
     # The ranges for the values in the solution vector.
@@ -14,7 +14,7 @@ struct GenericSplitFunction{fSetType <: Tuple, idxSetType <: Tuple, sSetType <:
     synchronizers::sSetType
     function GenericSplitFunction(fs::Tuple, drs::Tuple, syncers::Tuple)
         @assert length(fs) == length(drs) == length(syncers)
-        new{typeof(fs), typeof(drs), typeof(syncers)}(fs, drs, syncers)
+        return new{typeof(fs), typeof(drs), typeof(syncers)}(fs, drs, syncers)
     end
 end
 
@@ -28,7 +28,7 @@ Indicator that no synchronization between parameters and solution vectors is nec
 struct NoExternalSynchronization end
 
 function GenericSplitFunction(fs::Tuple, drs::Tuple)
-    GenericSplitFunction(fs, drs, ntuple(_->NoExternalSynchronization(), length(fs)))
+    return GenericSplitFunction(fs, drs, ntuple(_ -> NoExternalSynchronization(), length(fs)))
 end
 
 @inline get_operator(f::GenericSplitFunction, i::Integer) = f.functions[i]