chore: add VERSION file and Bump-Version.ps1 script

Single source of truth for version numbers. Bump-Version.ps1 replaces
the old version across all 61 files (113 occurrences) automatically.
CHANGELOG.md is excluded to preserve historical entries.

Usage:
  .\Tools\Bump-Version.ps1 -NewVersion "2.2.4" -DryRun  # preview
  .\Tools\Bump-Version.ps1 -NewVersion "2.2.4"           # apply

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Tools/Bump-Version.ps1

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+#Requires -Version 5.1
+
+<#
+.SYNOPSIS
+    Bump version number across all project files
+
+.DESCRIPTION
+    Reads the current version from the VERSION file, replaces it with the new
+    version in all project files, and updates the VERSION file.
+
+    CHANGELOG.md is excluded because it contains historical version entries
+    that must not be modified.
+
+.PARAMETER NewVersion
+    The new version number (e.g., "2.2.4")
+
+.PARAMETER DryRun
+    Preview changes without modifying any files
+
+.EXAMPLE
+    .\Bump-Version.ps1 -NewVersion "2.2.4"
+    Bump all files from current version to 2.2.4
+
+.EXAMPLE
+    .\Bump-Version.ps1 -NewVersion "2.2.4" -DryRun
+    Preview what would change without modifying files
+
+.NOTES
+    Author: NexusOne23
+    The VERSION file at the project root is the single source of truth.
+#>
+
+[CmdletBinding()]
+param(
+    [Parameter(Mandatory = $true)]
+    [ValidatePattern('^\d+\.\d+\.\d+$')]
+    [string]$NewVersion,
+
+    [switch]$DryRun
+)
+
+$ErrorActionPreference = 'Stop'
+
+# Resolve project root (one level up from Tools/)
+$projectRoot = Split-Path $PSScriptRoot -Parent
+$versionFile = Join-Path $projectRoot "VERSION"
+
+# Read current version
+if (-not (Test-Path $versionFile)) {
+    Write-Host "ERROR: VERSION file not found at: $versionFile" -ForegroundColor Red
+    exit 1
+}
+
+$oldVersion = (Get-Content $versionFile -Raw).Trim()
+
+if (-not ($oldVersion -match '^\d+\.\d+\.\d+$')) {
+    Write-Host "ERROR: Invalid version in VERSION file: '$oldVersion'" -ForegroundColor Red
+    exit 1
+}
+
+if ($oldVersion -eq $NewVersion) {
+    Write-Host "ERROR: New version ($NewVersion) is identical to current version ($oldVersion)" -ForegroundColor Red
+    exit 1
+}
+
+# File extensions to process
+$extensions = @("*.ps1", "*.psm1", "*.psd1", "*.json", "*.md", "*.bat", "*.yml")
+
+# Files to exclude (relative to project root)
+$excludedFiles = @("CHANGELOG.md")
+
+Write-Host ""
+Write-Host "========================================" -ForegroundColor Cyan
+Write-Host "  NoID Privacy Version Bump" -ForegroundColor Cyan
+Write-Host "========================================" -ForegroundColor Cyan
+Write-Host ""
+Write-Host "  Current version:  $oldVersion" -ForegroundColor White
+Write-Host "  New version:      $NewVersion" -ForegroundColor Green
+Write-Host ""
+
+if ($DryRun) {
+    Write-Host "  [DRY RUN - No files will be modified]" -ForegroundColor Yellow
+    Write-Host ""
+}
+
+# Collect all matching files
+$allFiles = @()
+foreach ($ext in $extensions) {
+    $allFiles += Get-ChildItem -Path $projectRoot -Filter $ext -Recurse -File |
+        Where-Object { $_.FullName -notmatch '[\\/]\.git[\\/]' }
+}
+
+# Process files
+$changedFiles = 0
+$totalReplacements = 0
+
+foreach ($file in $allFiles) {
+    $relativePath = $file.FullName.Substring($projectRoot.Length + 1)
+
+    # Check exclusion list
+    $isExcluded = $false
+    foreach ($excluded in $excludedFiles) {
+        if ($relativePath -eq $excluded) {
+            $isExcluded = $true
+            break
+        }
+    }
+    if ($isExcluded) {
+        Write-Host "  [SKIP] $relativePath (excluded)" -ForegroundColor DarkGray
+        continue
+    }
+
+    # Read file content
+    $content = Get-Content $file.FullName -Raw -Encoding UTF8
+
+    # Count occurrences
+    $count = ([regex]::Matches($content, [regex]::Escape($oldVersion))).Count
+
+    if ($count -gt 0) {
+        $changedFiles++
+        $totalReplacements += $count
+
+        Write-Host "  [BUMP] $relativePath ($count replacement$(if ($count -gt 1) {'s'}))" -ForegroundColor Green
+
+        if (-not $DryRun) {
+            $newContent = $content.Replace($oldVersion, $NewVersion)
+            [System.IO.File]::WriteAllText($file.FullName, $newContent, [System.Text.UTF8Encoding]::new($false))
+        }
+    }
+}
+
+# Update VERSION file
+if (-not $DryRun) {
+    [System.IO.File]::WriteAllText($versionFile, "$NewVersion`n", [System.Text.UTF8Encoding]::new($false))
+}
+
+# Summary
+Write-Host ""
+Write-Host "========================================" -ForegroundColor Cyan
+Write-Host "  Summary" -ForegroundColor Cyan
+Write-Host "========================================" -ForegroundColor Cyan
+Write-Host ""
+Write-Host "  Files changed:     $changedFiles" -ForegroundColor White
+Write-Host "  Total replacements: $totalReplacements" -ForegroundColor White
+Write-Host ""
+
+if ($DryRun) {
+    Write-Host "  DRY RUN complete. No files were modified." -ForegroundColor Yellow
+    Write-Host "  Run without -DryRun to apply changes." -ForegroundColor Yellow
+}
+else {
+    Write-Host "  Version bumped: $oldVersion -> $NewVersion" -ForegroundColor Green
+    Write-Host ""
+    Write-Host "  Next steps:" -ForegroundColor White
+    Write-Host "    1. Update CHANGELOG.md with new version section" -ForegroundColor Gray
+    Write-Host "    2. Review changes: git diff" -ForegroundColor Gray
+    Write-Host "    3. Commit: git add -A && git commit -m 'chore: bump version to $NewVersion'" -ForegroundColor Gray
+}
+
+Write-Host ""

VERSION

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+2.2.3