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/include/cli.h

@@ -0,0 +1,107 @@
+/*
+  StarForth — Steady-State Virtual Machine Runtime
+
+  Copyright (c) 2023–2025 Robert A. James
+  All rights reserved.
+
+  This file is part of the StarForth project.
+
+  Licensed under the StarForth License, Version 1.0 (the "License");
+  you may not use this file except in compliance with the License.
+
+  You may obtain a copy of the License at:
+      https://github.com/star.4th@proton.me/StarForth/LICENSE.txt
+
+  This software is provided "AS IS", WITHOUT WARRANTY OF ANY KIND,
+  express or implied, including but not limited to the warranties of
+  merchantability, fitness for a particular purpose, and noninfringement.
+
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+ StarForth — Steady-State Virtual Machine Runtime
+  Copyright (c) 2023–2025 Robert A. James
+  All rights reserved.
+
+  This file is part of the StarForth project.
+
+  Licensed under the StarForth License, Version 1.0 (the "License");
+  you may not use this file except in compliance with the License.
+
+  You may obtain a copy of the License at:
+       https://github.com/star.4th@proton.me/StarForth/LICENSE.txt
+
+  This software is provided "AS IS", WITHOUT WARRANTY OF ANY KIND,
+  express or implied, including but not limited to the warranties of
+  merchantability, fitness for a particular purpose, and noninfringement.
+
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+ */
+
+#ifndef STARFORTH_CLI_H
+#define STARFORTH_CLI_H
+
+#include <stdint.h>
+#include "log.h"
+
+/**
+ * @brief Heartbeat logging modes for DoE experiments
+ */
+typedef enum {
+    HEARTBEAT_LOG_OFF = 0,     /* No heartbeat output, only final summary */
+    HEARTBEAT_LOG_SUMMARY = 1, /* Bucket aggregates every N ticks */
+    HEARTBEAT_LOG_FULL = 2     /* Per-tick CSV output to hb/run-<id>.csv */
+} HeartbeatLogMode;
+
+/**
+ * @brief Configuration structure from command-line arguments
+ * Consolidates all parsed CLI options into a single, cleanly organized struct
+ */
+typedef struct
+{
+    /* Test modes */
+    int run_tests;
+    int break_me;
+    int fail_fast;
+
+    /* Benchmark mode */
+    int benchmark;
+    int benchmark_iterations;
+
+    /* Design of Experiments mode */
+    int doe_experiment;  /* 1 if --doe-experiment flag set, run harness once and collect metrics */
+    HeartbeatLogMode heartbeat_log_mode; /* off|summary|full for DoE time-series data */
+
+    /* REPL mode */
+    int script_mode;  /* -s: silent/script mode (no prompts, no "ok" output) */
+
+    /* Logging */
+    LogLevel log_level;
+    int log_level_explicitly_set;
+
+    /* Block I/O */
+    const char* disk_img_path;
+    uint32_t ram_disk_mb;
+
+    /* Legacy flags (internal use) */
+    int run_tests_flag_observed;
+} CLIConfig;
+
+/**
+ * @brief Parse command-line arguments into CLIConfig
+ *
+ * @param argc Argument count
+ * @param argv Argument vector
+ * @return CLIConfig struct with parsed options, or exits on --version/--help
+ */
+CLIConfig cli_parse(int argc, char* argv[]);
+
+/**
+ * @brief Print usage/help information
+ * @param program_name Name of the executable
+ */
+void cli_print_usage(const char* program_name);
+
+#endif /* STARFORTH_CLI_H */