PHLEGM v9 Revision r6 — Native Linux PCRE2 packaging and loader

Source baseline: PHLEGM v9 r5 (PCRE2 Windows runtime build/packaging).

Changes:
- Shared regex.lib dynamically loads architecture-qualified Linux PCRE2 from ExePath
  before falling back to the system libpcre2-8.so.0 / libpcre2-8.so.
- Linux x86    : PCRE2-Linux-x86.so.0 (ELF32/EM_386).
- Linux x86_64 : PCRE2-Linux-x86_64.so.0 (ELF64/EM_X86_64).
- Combined Linux x86/x86_64 archives can carry both .so variants in one root.
- Native Linux resolver searches explicit environment overrides, build/runtime/
  architecture caches, ldconfig entries, common multiarch directories, and
  LD_LIBRARY_PATH. It validates ELF identity and required PCRE2 symbols.
- Runtime discovery and its PCRE2 license must succeed before the compiler
  packaging step can pass. Invalid/missing x86 dependencies fail explicitly.
- End User ZIP verification requires each selected Linux .so and the Linux
  license. Unselected Linux .so and Windows DLLs are rejected in minimal ZIPs.
- Native-Linux-Compile.sh stages the Linux PCRE2 library beside its ELF output.
- Windows PCRE2-32.dll/PCRE2-64.dll acquisition and packaging are unchanged.
- regex.lib remains generic; parser schemas live in definition-parser.bi;
  FBVM remains embedded within aa.lib.

User-controlled offline sources:
  PHLEGM_PCRE2_LINUX_X86=/absolute/path/to/32-bit/libpcre2-8.so.0
  PHLEGM_PCRE2_LINUX_X86_64=/absolute/path/to/64-bit/libpcre2-8.so.0
  build/runtime/Linux-x86/PCRE2-Linux-x86.so.0
  build/runtime/Linux-x86_64/PCRE2-Linux-x86_64.so.0
  (cache requires an accompanying PCRE2-Linux-LICENSE.txt, or an installed
   system redistributable license in a standard distro location.)

Dependencies: bash, od, readelf (or nm); native PCRE2 library for each selected
Linux bitness. On Debian, x86 may require libpcre2-8-0:i386 and a multiarch setup.
Do not attempt to use a Windows DLL as a Linux .so. Linux system library
compatibility across distributions is not guaranteed; use host-compatible
libraries (glibc/musl/version matters). Loader falls back to system PCRE2 if
packaged .so cannot be loaded.

Validation in this environment:
- Resolver x86_64 discovery and caching: PASS (host native PCRE2).
- x86_64 ELF Class/Machine and PCRE2 API exports: PASS.
- Linux redistribution license copied: PASS.
- Deliberate x86<-x86_64 ELF mismatch rejected: PASS.
- Unrelated libm.so.6 rejected for absent PCRE2 exports: PASS.
- bash -n for modified scripts: PASS.
- Native FreeBASIC compiler/pwsh unavailable: full Linux builds, End User ZIP
  creation through PowerShell, and runtime emulation remain UNVERIFIED.
- Native x86 PCRE2 absent in this environment; x86 success not verified.
- Windows native compilation and PCRE2 DLL loading not re-tested in r6.

Smoke test: tools/native-tests/linux-pcre2-runtime-smoke.sh
Compile/runtime tests: tools/Compile-AA-Regex.sh; tools/Native-Linux-Compile.sh
No Python scripts or dependencies are included in Developer/End-User distributions.
