chore: archive early implementations and chunk checker tools

tools/Makefile

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+CXX ?= g++
+CXXFLAGS ?= -O3 -std=c++17 -fwrapv
+.PHONY: all clean
+all: bin/sliming
+bin/sliming: sliming.cpp
+	mkdir -p bin
+	$(CXX) $(CXXFLAGS) $< -o $@
+clean:
+	rm -f bin/sliming

tools/README.md

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+# 小工具与历史参考
+
+`sliming.cpp` 是从根目录归档过来的单区块 Java 随机数检查工具，算法未改动。
+
+```sh
+make tools
+./tools/bin/sliming 61692151016558 51069 419124
+```
+
+`reference/sliming.s` 保留先前的汇编快照，供研究编译器输出时参考；它不是从当前源码重新生成的产物，不参与构建。原根目录的旧 `sliming` 可执行文件已被忽略，可通过 `make clean` 清理。

tools/reference/sliming.s

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+	.file	"sliming.cpp"
+	.text
+	.p2align 4
+	.globl	_Z12isSlimeChunklii
+	.type	_Z12isSlimeChunklii, @function
+_Z12isSlimeChunklii:
+.LFB7:
+	.cfi_startproc
+	endbr64
+	movl	%esi, %eax
+	movl	%edx, %ecx
+	imull	%esi, %eax
+	imull	%edx, %ecx
+	imull	$5947611, %esi, %esi
+	imull	$4987142, %eax, %eax
+	movslq	%ecx, %rcx
+	imull	$389711, %edx, %edx
+	imulq	$4392871, %rcx, %rcx
+	movslq	%esi, %rsi
+	cltq
+	addq	%rdi, %rax
+	movslq	%edx, %rdx
+	addq	%rsi, %rax
+	addq	%rcx, %rax
+	addq	%rdx, %rax
+	movabsq	$25303508018, %rdx
+	xorq	%rdx, %rax
+	movabsq	$281474976710655, %rdx
+	andq	%rdx, %rax
+	movabsq	$25214903917, %rdx
+	imulq	%rdx, %rax
+	addq	$11, %rax
+	shrq	$17, %rax
+	andl	$2147483647, %eax
+	imull	$-858993459, %eax, %eax
+	rorl	%eax
+	cmpl	$429496729, %eax
+	setbe	%al
+	ret
+	.cfi_endproc
+.LFE7:
+	.size	_Z12isSlimeChunklii, .-_Z12isSlimeChunklii
+	.section	.text.startup,"ax",@progbits
+	.p2align 4
+	.globl	main
+	.type	main, @function
+main:
+.LFB8:
+	.cfi_startproc
+	endbr64
+	xorl	%eax, %eax
+	ret
+	.cfi_endproc
+.LFE8:
+	.size	main, .-main
+	.ident	"GCC: (Ubuntu 13.3.0-6ubuntu2~24.04.1) 13.3.0"
+	.section	.note.GNU-stack,"",@progbits
+	.section	.note.gnu.property,"a"
+	.align 8
+	.long	1f - 0f
+	.long	4f - 1f
+	.long	5
+0:
+	.string	"GNU"
+1:
+	.align 8
+	.long	0xc0000002
+	.long	3f - 2f
+2:
+	.long	0x3
+3:
+	.align 8
+4:

tools/sliming.cpp

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+#pragma GCC optimize("wrapv")
+
+#include <cstdint>
+
+struct JavaRandom {
+    int64_t seed;
+
+    JavaRandom(int64_t seed) : seed((seed ^ 0x5DEECE66DLL) & ((1LL << 48) - 1)) {}
+
+    int32_t next(int bits) {
+        seed = (seed * 0x5DEECE66DLL + 0xBLL) & ((1LL << 48) - 1);
+        return (int32_t)((uint64_t)seed >> (48 - bits));
+    }
+
+    int32_t nextInt(int32_t n) {
+        if ((n & -n) == n)  // n is a power of 2
+            return (int32_t)((n * (int64_t)next(31)) >> 31);
+
+        int32_t bits, val;
+        do {
+            bits = next(31);
+            val = bits % n;
+        } while (bits - val + (n - 1) < 0);
+        return val;
+
+    }
+};
+
+bool isSlimeChunk(int64_t worldSeed, int32_t chunkX, int32_t chunkZ) {
+    int64_t seed = worldSeed +
+                   (int64_t)(chunkX * chunkX * 4987142) +
+                   (int64_t)(chunkX * 5947611) +
+                   (int64_t)(chunkZ * chunkZ) * 4392871LL +
+                   (int64_t)(chunkZ * 389711) ^ 987234911LL;
+    JavaRandom rand(seed);
+    return rand.nextInt(10) == 0;
+}
+
+#include <cstdio>
+#include <cstdlib>
+
+
+int main(int argc, char *argv[]) {
+    if (argc != 4) {
+        return 1;
+    }
+    int64_t worldSeed = atoll(argv[1]);
+    int32_t chunkX = atoi(argv[2]);
+    int32_t chunkZ = atoi(argv[3]);
+    bool isSlime = isSlimeChunk(worldSeed, chunkX, chunkZ);
+    printf("Is Slime Chunk: %s\n", isSlime ? "true" : "false");
+    return 0;
+}