Map the world view sizing; add RE tooling

- docs/widescreen.md: render-thread frame, cWorldView0 layout and methods,
  view size = zoom * 1024.0/768.0 float constants and all their users,
  ortho projection extents, open questions (activity radius, buffers).
- tools: find-imm (immediate/regex instruction search), rtti (vtables via
  MSVC RTTI), decompile.ps1 + Ghidra scripts for a persistent project;
  ApplyRtti recovers 410 vtables / ~1200 functions Ghidra misses.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

tools/decompile.ps1

@@ -0,0 +1,26 @@
+# Decompile addresses from the persistent Ghidra project (ghidra/sacred.gpr).
+#   .\tools\decompile.ps1 0x6322b0 0x62ae70 [-Out file.c] [-ReadOnly]
+# Prints the C to stdout (and keeps it in -Out, default ghidra\last.c).
+# Without -ReadOnly, functions created for vtable-only methods are saved.
+param(
+    [Parameter(Mandatory, ValueFromRemainingArguments)][string[]]$Addresses,
+    [string]$Out = "",
+    [switch]$ReadOnly
+)
+$ErrorActionPreference = "Stop"
+$root = Split-Path $PSScriptRoot
+if (-not $Out) { $Out = Join-Path $root "ghidra\last.c" }
+$ghidra = if ($env:GHIDRA_INSTALL_DIR) { $env:GHIDRA_INSTALL_DIR } else { "E:\Coding\Ghidra\ghidra_12.1.4_PUBLIC" }
+if (-not $env:JAVA_HOME) { $env:JAVA_HOME = "C:\Program Files\Java\jdk-21" }
+
+$arguments = @(
+    (Join-Path $root "ghidra"), "sacred",
+    "-process", "sacred.exe", "-noanalysis",
+    "-scriptPath", (Join-Path $PSScriptRoot "ghidra"),
+    "-postScript", "Decompile.java", $Out
+) + $Addresses
+if ($ReadOnly) { $arguments += "-readOnly" }
+
+& (Join-Path $ghidra "support\analyzeHeadless.bat") @arguments *> (Join-Path $root "ghidra\decompile.out")
+if ($LASTEXITCODE -ne 0) { Get-Content (Join-Path $root "ghidra\decompile.out") -Tail 30; exit $LASTEXITCODE }
+Get-Content $Out