feat(sub-lang): Integrate SUB Language (.sb) native kernel modules and in-kernel VM/interpreter

- Add native .sb kernel modules in sub/ (signature.sb, power_governor.sb, benchmark.sb, easter_egg.sb)
- Implement in-kernel SUB Language VM and AST interpreter in kernel/sub/sub_vm.c
- Implement C-interop runtime in kernel/sub/sub_runtime.c and include/kernel/sub_lang.h
- Initialize SUB Language Engine in boot sequence step [8/14] in kernel/main.c
- Implement strtol in lib/string.c
- Add LazyBox applets: 'subinfo', 'subi', 'subpower', 'subbench', and 'subquote'

include/kernel/sub_lang.h

@@ -0,0 +1,30 @@
+#ifndef _KERNEL_SUB_LANG_H
+#define _KERNEL_SUB_LANG_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+// Core Engine Initialization & Signature
+int sub_kernel_init(void);
+const char* sub_get_os_signature(void);
+const char* sub_get_sub_lang_version(void);
+const char* sub_get_author_credits(void);
+void sub_kernel_print_signature(void);
+
+// CPU Power Governor & Thermal Scaling Engine
+int sub_power_calc_pstate(int32_t temp_celsius, uint32_t cpu_load_pct);
+uint32_t sub_power_get_freq_mhz(int pstate);
+uint32_t sub_power_get_voltage_mv(int pstate);
+
+// Algorithm & Math Benchmark
+uint32_t sub_benchmark_run(uint32_t iterations);
+
+// Easter Eggs & Kernel Quotes
+const char* sub_easter_egg_get(int idx);
+
+// In-Kernel Interpreter & Virtual Machine
+int sub_vm_eval_string(const char* code);
+int sub_vm_eval_file(const char* filepath);
+
+#endif // _KERNEL_SUB_LANG_H