Reorganize source tree: kernel/, v3/, v4/ split and board infrastructure

Source tree reorganization:
- Move StarForth v3 engine to v3/ (src/, include/, Makefile)
- Move kernel to kernel/ (src/, include/, linker/, Makefile)
- Create v4/ skeleton for F18-ISA golden model (DECOMPOSITION.md, JUSTIFICATION.md)
- Move FABRIC-0..4.md to docs/fabric/
- Move ONTOLOGY.md and ROADMAP.md to docs/

Board infrastructure:
- Add boards/ser5/, boards/raspi/, boards/milkv/, boards/zynq7020/
- Each board has board.mk (ISA, CPU flags, boot recipe) and README.md
- Root Makefile becomes thin dispatcher: boot_image, all, clean, docs take TARGET
- make boot_image TARGET=SER5|RASPI|MILKV builds one GPT/MBR image per board
- ZYNQ7020 target exists but stops with clear error (ARMv7 port not built yet)
- scripts/mkdiskimage.sh builds disk images for all boards

Docs pipeline:
- docs/book/ with LaTeX master (main.tex) and Makefile
- pandoc converts Markdown to LaTeX at build time
- Two Lua filters: table-widths.lua (wide tables wrap), code-breaks.lua (inline code breaks)
- make docs builds single PDF (754 pages, 0 missing characters)
- make docs TARGET=<board> adds board appendix
- build/docs/<book|board>/meta.tex stamps git commit into PDF

Bug fixes:
- 42 include paths that only worked by accident now use correct relative paths
- clang-18 hardcode replaced with configurable CC variable (fixed aarch64 build)
- Pi 5: kernel_2712.img linked at 0x80000, .bss zeroed, memory reserved
- Doxyfile, .clang-tidy, README.md, Kconfig paths updated

Verified:
- Hosted v3 build passes 1012 tests, 0 failures
- SER5 image boots in QEMU (OVMF), POST passes, K exact (65536 = Q48_ONE)
- Milk-V image boots in QEMU (OpenSBI + U-Boot + bootefi), POST passes
- make clean TARGET=<board> removes only that board and its ISA objects
- make all builds all boards, hosted v3, and docs in one run

Co-authored-by: Junie <junie@jetbrains.com>

v3/src/word_source/lifecycle_words_hosted.c

@@ -0,0 +1,89 @@
+/*
+  StarForth — Steady-State Virtual Machine Runtime
+
+  Copyright (c) 2023–2025 Robert A. James
+  All rights reserved.
+
+  Licensed under the StarForth License, Version 1.0
+*/
+
+/**
+ * lifecycle_words_hosted.c - BIRTH KILL PAUSE RESUME USE for hosted Linux build
+ *
+ * Hosted-build counterpart to src/starkernel/capsule/lifecycle_words.c.
+ * All five words are ( c-addr u -- ), stack-clean, errors logged not pushed.
+ *
+ * In the hosted build there is no capsule blob or kernel VM registry, so
+ * these implementations consume their arguments and log intent.  The kernel
+ * build (compiled with -D__STARKERNEL__) skips this file entirely because
+ * the Makefile glob does not include src/word_source/ for that target.
+ */
+
+#ifndef __STARKERNEL__
+
+#include "../../include/vm.h"
+#include "../../include/word_registry.h"
+#include "../../include/log.h"
+
+#include <string.h>
+
+#define NAME_MAX_LEN 64
+
+static void extract_name(VM *vm, cell_t caddr, cell_t u, char *out, int max) {
+    int len = (int)u;
+    if (len >= max) len = max - 1;
+    if (len < 0)    len = 0;
+    if (len > 0 && caddr < (cell_t)VM_MEMORY_SIZE)
+        memcpy(out, (const char *)vm->memory + caddr, (size_t)len);
+    out[len] = '\0';
+}
+
+static void hosted_lifecycle_birth(VM *vm) {
+    cell_t u     = vm_pop(vm);
+    cell_t caddr = vm_pop(vm);
+    char name[NAME_MAX_LEN];
+    extract_name(vm, caddr, u, name, NAME_MAX_LEN);
+    log_message(LOG_INFO, "BIRTH %s (hosted)", name);
+}
+
+static void hosted_lifecycle_kill(VM *vm) {
+    cell_t u     = vm_pop(vm);
+    cell_t caddr = vm_pop(vm);
+    char name[NAME_MAX_LEN];
+    extract_name(vm, caddr, u, name, NAME_MAX_LEN);
+    log_message(LOG_INFO, "KILL %s (hosted)", name);
+}
+
+static void hosted_lifecycle_pause(VM *vm) {
+    cell_t u     = vm_pop(vm);
+    cell_t caddr = vm_pop(vm);
+    char name[NAME_MAX_LEN];
+    extract_name(vm, caddr, u, name, NAME_MAX_LEN);
+    log_message(LOG_INFO, "PAUSE %s (hosted)", name);
+}
+
+static void hosted_lifecycle_resume(VM *vm) {
+    cell_t u     = vm_pop(vm);
+    cell_t caddr = vm_pop(vm);
+    char name[NAME_MAX_LEN];
+    extract_name(vm, caddr, u, name, NAME_MAX_LEN);
+    log_message(LOG_INFO, "RESUME %s (hosted)", name);
+}
+
+static void hosted_lifecycle_use(VM *vm) {
+    cell_t u     = vm_pop(vm);
+    cell_t caddr = vm_pop(vm);
+    char name[NAME_MAX_LEN];
+    extract_name(vm, caddr, u, name, NAME_MAX_LEN);
+    log_message(LOG_INFO, "USE %s (hosted)", name);
+}
+
+void register_lifecycle_words(VM *vm) {
+    register_word(vm, "BIRTH",  hosted_lifecycle_birth);
+    register_word(vm, "KILL",   hosted_lifecycle_kill);
+    register_word(vm, "PAUSE",  hosted_lifecycle_pause);
+    register_word(vm, "RESUME", hosted_lifecycle_resume);
+    register_word(vm, "USE",    hosted_lifecycle_use);
+}
+
+#endif /* !__STARKERNEL__ */