chore: Add powershell script for clang-formatting (#1472)

## Summary

* **What is the goal of this PR?** Add a windows equivalent for the
linux clang-format-fix script
* **What changes are included?**

## Additional Context
```
.SYNOPSIS
    Runs clang-format -i on project *.cpp and *.h files.

.DESCRIPTION
    Formats all C/C++ source and header files in the repository, excluding
    generated, vendored, and build directories (open-x4-sdk, builtinFonts,
    hyphenation tries, uzlib, .pio, *.generated.h).

    The clang-format binary path is resolved once and cached in
    .local/clang-format-fix.local. On first run it checks a default path,
    then PATH, then common install locations. Edit the .local file to
    override manually.

.PARAMETER g
    Format only git-modified files (git diff --name-only HEAD) instead of
    the full tree.

.PARAMETER h
    Show this help text.
```
---

### AI Usage

While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.

Did you use AI tools to help write this code? _**< YES >**_

bin/clang-format-fix.ps1

@@ -0,0 +1,154 @@
+<#
+.SYNOPSIS
+    Runs clang-format -i on project *.cpp and *.h files.
+
+.DESCRIPTION
+    Formats all C/C++ source and header files in the repository, excluding
+    generated, vendored, and build directories (open-x4-sdk, builtinFonts,
+    hyphenation tries, uzlib, .pio, *.generated.h).
+
+    The clang-format binary path is resolved once and cached in
+    bin/clang-format-fix.local. On first run it checks a default path,
+    then PATH, then common install locations. Edit the .local file to
+    override manually.
+
+.PARAMETER g
+    Format only git-modified files (git diff --name-only HEAD) instead of
+    the full tree.
+
+.PARAMETER h
+    Show this help text.
+
+.EXAMPLE
+    .\clang-format-fix.ps1
+    Format all files.
+
+.EXAMPLE
+    .\clang-format-fix.ps1 -g
+    Format only git-modified files.
+#>
+
+param(
+    [switch]$g,
+    [switch]$h
+)
+
+if ($h) {
+    Get-Help $PSCommandPath -Detailed
+    return
+}
+
+$repoRoot = (Resolve-Path "$PSScriptRoot\..").Path
+$configFile = Join-Path $PSScriptRoot 'clang-format-fix.local'
+$defaultPath = 'C:\Program Files\LLVM\bin\clang-format.exe'
+
+$candidatePaths = @(
+    'C:\Program Files\LLVM\bin\clang-format.exe'
+    'C:\Program Files (x86)\LLVM\bin\clang-format.exe'
+    'C:\msys64\ucrt64\bin\clang-format.exe'
+    'C:\msys64\mingw64\bin\clang-format.exe'
+    "$env:LOCALAPPDATA\LLVM\bin\clang-format.exe"
+)
+
+function Find-ClangFormat {
+    # Try PATH first
+    $inPath = Get-Command clang-format -ErrorAction SilentlyContinue
+    if ($inPath) { return $inPath.Source }
+
+    # Try candidate paths
+    foreach ($p in $candidatePaths) {
+        if (Test-Path $p) { return $p }
+    }
+    return $null
+}
+
+function Resolve-ClangFormat {
+    # 1. Read from config if present
+    if (Test-Path $configFile) {
+        $saved = (Get-Content $configFile -Raw).Trim()
+        if ($saved -and (Test-Path $saved)) { return $saved }
+        Write-Host "Configured path no longer valid: $saved"
+    }
+
+    # 2. Check default
+    if (Test-Path $defaultPath) {
+        $defaultPath | Set-Content $configFile
+        Write-Host "Saved clang-format path to $configFile"
+        return $defaultPath
+    }
+
+    # 3. Search PATH and candidate locations
+    $found = Find-ClangFormat
+    if ($found) {
+        $found | Set-Content $configFile
+        Write-Host "Found clang-format at $found - saved to $configFile"
+        return $found
+    }
+
+    Write-Error "clang-format not found. Install LLVM or add clang-format to PATH."
+    exit 1
+}
+
+$clangFormat = Resolve-ClangFormat
+
+$exclude = @(
+    'open-x4-sdk'
+    'lib\EpdFont\builtinFonts'
+    'lib\Epub\Epub\hyphenation\generated'
+    'lib\uzlib'
+    '.pio'
+)
+
+function Test-Excluded($fullPath) {
+    foreach ($ex in $exclude) {
+        if ($fullPath -like "*\$ex\*") { return $true }
+    }
+    if ($fullPath -like '*.generated.h') { return $true }
+    return $false
+}
+
+if ($g) {
+    # Only git-modified *.cpp / *.h files
+    # Covers both staged and unstaged changes
+    $files = @(git -C $repoRoot diff --name-only HEAD) +
+             @(git -C $repoRoot diff --name-only --cached) |
+        Sort-Object -Unique |
+        Where-Object { $_ -match '\.(cpp|h)$' } |
+        ForEach-Object { Get-Item (Join-Path $repoRoot $_) -ErrorAction SilentlyContinue } |
+        Where-Object { $_ -and -not (Test-Excluded $_.FullName) }
+} else {
+    $files = Get-ChildItem -Path $repoRoot -Recurse -Include *.cpp, *.h -File |
+        Where-Object { -not (Test-Excluded $_.FullName) }
+}
+
+$files = @($files)
+
+if ($files.Count -eq 0) {
+    Write-Host 'No files to format.'
+    return
+}
+
+Write-Host "Formatting $($files.Count) files..."
+$i = 0
+$changed = 0
+$failures = 0
+foreach ($f in $files) {
+    $i++
+    $rel = $f.FullName.Substring($repoRoot.Length + 1)
+    $hashBefore = (Get-FileHash $f.FullName -Algorithm MD5).Hash
+    & $clangFormat -i $f.FullName
+    if ($LASTEXITCODE -ne 0) {
+        $failures++
+        Write-Host "  [$i/$($files.Count)] $rel (FAILED, exit code $LASTEXITCODE)"
+        continue
+    }
+    $hashAfter = (Get-FileHash $f.FullName -Algorithm MD5).Hash
+    if ($hashBefore -ne $hashAfter) {
+        $changed++
+        Write-Host "  [$i/$($files.Count)] $rel (changed)"
+    } else {
+        Write-Host "  [$i/$($files.Count)] $rel"
+    }
+}
+Write-Host "Done. $changed/$($files.Count) files changed, $failures failed."
+if ($failures -gt 0) { exit 1 }