fix(pproc): 修复预处理器对空行的处理逻辑

- 移除了错误的ENDLINE类型提前返回逻辑
- 将ENDLINE类型的处理移到正确的位置
- 添加了针对条件编译中空行的测试用例

fix(cli): 更新include路径参数的帮助文本

- 修正英文帮助文本为"Add directory to the include search paths"
- 修正中文帮助文本为"添加系统头文件到搜索路径"

libs/pproc/src/scc_pproc.c

@@ -20,11 +20,6 @@ CONTINUE:
     if (ok == false) {
         return false;
     }
-    if (tok.type == SCC_TOK_ENDLINE) {
-        scc_ring_next_consume(*stream, *out, ok);
-        pp->at_line_start = true;
-        return true;
-    }
 
     if (pp->at_line_start) {
         if (tok.type == SCC_TOK_SHARP) {
@@ -51,7 +46,11 @@ CONTINUE:
         goto CONTINUE;
     }
 
-    if (tok.type == SCC_TOK_IDENT) {
+    if (tok.type == SCC_TOK_ENDLINE) {
+        scc_ring_next_consume(*stream, *out, ok);
+        pp->at_line_start = true;
+        return true;
+    } else if (tok.type == SCC_TOK_IDENT) {
         // maybe expanded
         scc_pproc_macro_t *macro =
             scc_pproc_macro_table_get(&pp->macro_table, &tok.lexeme);

libs/pproc/tests/test_unit.c

@@ -273,6 +273,24 @@ static void test_conditional_ifdef(void) {
                           "#endif\n",
                           "foo\n");
 
+    CHECK_PP_OUTPUT_EXACT("#ifdef FOO\n"
+                          "\n"
+                          "#endif\n",
+                          "");
+
+    CHECK_PP_OUTPUT_EXACT("#ifdef FOO\n"
+                          "#endif\n",
+                          "");
+
+    CHECK_PP_OUTPUT_EXACT("#ifndef FOO\n"
+                          "\n"
+                          "#endif\n",
+                          "\n");
+
+    CHECK_PP_OUTPUT_EXACT("#ifndef FOO\n"
+                          "#endif\n",
+                          "");
+
     // ifdef + else
     CHECK_PP_OUTPUT_EXACT("#define FOO\n"
                           "#ifdef FOO\n"