Add headless parallel eu7v2 scenario bake with streaming and PLCE placements

Enable --eu7v2-bake from the main binary: parallel module pool, bounded-RAM
spool flush, streaming terrain triangles, flat include/model parsing, and
eu7v2 emit/load with optional verify. Large placement .scm files emit lean
PLCE records and bake referenced .inc modules separately for reuse.

- CLI: --eu7v2-bake, --eu7v2-verify, --eu7v2-mem-limit-gb, --eu7v2-threads,
  --eu7v2-max-parse; wire max_threads through to the bake parser
- eu7v2 v2 records: PLCE placements, runtime emitter/loader, batch verify
- Parallel bake pool with session cache; drop heavy-serial parse gate in spool
  mode; parse concurrency matches thread count
- Streaming terrain: batched parallel parse+bake, scan/bake pipeline, shape
  spool with persistent buffered I/O and flush-before-read
- Parallel flat-file streaming for models/includes; pack/model spool for
  low-memory incremental flush
- Optional 50 GB private-bytes guard during headless bake

Braniewo_szeroki: 160 modules, verify PASS, ~34s bake (nmt100 ~17s vs ~190s
serial baseline).

Co-authored-by: Cursor <cursoragent@cursor.com>

EU07.cpp

@@ -21,6 +21,7 @@ Stele, firleju, szociu, hunter, ZiomalCl, OLI_EU and others
 #include "application/application.h"
 #include "utilities/Logs.h"
 #include <cstdlib>
+#include <iostream>
 #ifdef WITHDUMPGEN
 #ifdef _WIN32
 #include <Windows.h>
@@ -89,6 +90,14 @@ int main(int argc, char *argv[])
 	// init start timestamp
 	Global.startTimestamp = std::chrono::steady_clock::now();
 
+	// headless short-circuit: text -> eu7v2 bake (+optional verify), no window
+	if (eu07_application::wants_eu7v2_headless(argc, argv))
+	{
+		int const code{eu07_application::run_eu7v2_headless(argc, argv)};
+		std::cout.flush();
+		std::_Exit(code);
+	}
+
 	// quick short-circuit for standalone e3d export
 	if (argc == 6 && std::string(argv[1]) == "-e3d")
 	{