Phase 0: fix runtime script compilation

ScriptCompiler.Compile() runs `dotnet build Scripts/Scripts.csproj -c Release`
with no Platform, so MSBuild defaults to AnyCPU. Scripts.csproj gated both
OutputPath and DefineConstants on Configuration|Platform == Release|x64, so
under the server's own build the DLL landed in Scripts/bin/Release/ (while the
core loads Scripts.dll from the base directory) and TRACE;NEWTIMERS;ServUO went
undefined (XmlSpawner compiled its non-ServUO branches).

Compile() also never checks the build's exit code before Assembly.LoadFrom, so
the failure was silent and the stale DLL reloaded. Runtime script compilation
had had no effect since 2026-05-30.

Condition both property groups on Configuration alone. Server.csproj is left
alone: nothing under Server/ uses those symbols, and giving it OutputPath=..\
would make the boot-time build try to overwrite the running ServUO.exe.

Verified end-to-end: a plain boot now logs "Core: Compiling scripts... / Build
succeeded." and loads 206208 items, 42771 mobiles.

Also adds the implementation plan, the measured performance budget, the test
scaffolding used to produce it (seeder + probe, both default-off), and the
record of shard repairs that had to precede any of this.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

deploy.ps1

@@ -0,0 +1,75 @@
+<#
+.SYNOPSIS
+    Copies overlay/ into a ServUO server root.
+
+.DESCRIPTION
+    overlay/ mirrors the server root exactly, so deployment is a straight file copy.
+    Nothing is deleted from the server; this only adds or overwrites.
+
+    Run with -Verify first. It reports what would change and touches nothing.
+
+.EXAMPLE
+    .\deploy.ps1 -ServerPath C:\Users\colby\Desktop\servuo -Verify
+    .\deploy.ps1 -ServerPath C:\Users\colby\Desktop\servuo
+#>
+[CmdletBinding()]
+param(
+    [Parameter(Mandatory = $true)]
+    [string] $ServerPath,
+
+    [switch] $Verify
+)
+
+$ErrorActionPreference = 'Stop'
+
+$overlay = Join-Path $PSScriptRoot 'overlay'
+
+if (-not (Test-Path $overlay))    { throw "overlay/ not found next to deploy.ps1" }
+if (-not (Test-Path $ServerPath)) { throw "server path not found: $ServerPath" }
+
+# ServUO.exe holds a lock on Scripts.dll and writes Saves/ on exit. Never deploy under it.
+if (Get-Process -Name ServUO -ErrorAction SilentlyContinue) {
+    throw "ServUO is running. Stop it before deploying."
+}
+
+function Get-Sha([string] $path) {
+    if (-not (Test-Path $path)) { return $null }
+    return (Get-FileHash $path -Algorithm SHA256).Hash
+}
+
+$added = 0; $changed = 0; $same = 0
+
+Get-ChildItem $overlay -Recurse -File | ForEach-Object {
+    $rel = $_.FullName.Substring($overlay.Length + 1)
+    $dst = Join-Path $ServerPath $rel
+
+    $srcHash = Get-Sha $_.FullName
+    $dstHash = Get-Sha $dst
+
+    if ($null -eq $dstHash) {
+        $state = 'ADD    '; $added++
+    } elseif ($srcHash -ne $dstHash) {
+        $state = 'CHANGE '; $changed++
+    } else {
+        $state = 'same   '; $same++
+    }
+
+    if ($state -ne 'same   ') {
+        Write-Output "$state $rel"
+    }
+
+    if (-not $Verify -and $state -ne 'same   ') {
+        $parent = Split-Path $dst -Parent
+        if (-not (Test-Path $parent)) { New-Item -ItemType Directory -Force -Path $parent | Out-Null }
+        Copy-Item $_.FullName -Destination $dst -Force
+    }
+}
+
+Write-Output ""
+if ($Verify) {
+    Write-Output "VERIFY only. add=$added change=$changed unchanged=$same  (nothing written)"
+} else {
+    Write-Output "deployed. add=$added change=$changed unchanged=$same"
+    Write-Output ""
+    Write-Output "Scripts.csproj changed => next boot rebuilds Scripts.dll (Compiler.cfg Dynamic=True)."
+}