feat: split syscalls into files, change max process ceiling

kernel/src/Api/Heap.hpp

@@ -0,0 +1,39 @@
+/*
+    * Heap.hpp
+    * SYS_ALLOC, SYS_FREE syscalls
+    * Copyright (c) 2026 Daniel Hammer
+*/
+
+#include <cstdint>
+#include <Sched/Scheduler.hpp>
+#include <Memory/Paging.hpp>
+#include <Memory/HHDM.hpp>
+#include <Memory/PageFrameAllocator.hpp>
+
+namespace Zenith {
+    static uint64_t Sys_Alloc(uint64_t size) {
+        auto* proc = Sched::GetCurrentProcessPtr();
+        if (proc == nullptr) return 0;
+
+        // Round up to page boundary
+        size = (size + 0xFFF) & ~0xFFFULL;
+        if (size == 0) size = 0x1000;
+
+        uint64_t userVa = proc->heapNext;
+        uint64_t numPages = size / 0x1000;
+
+        for (uint64_t i = 0; i < numPages; i++) {
+            void* page = Memory::g_pfa->AllocateZeroed();
+            if (page == nullptr) return 0;
+            uint64_t physAddr = Memory::SubHHDM((uint64_t)page);
+            Memory::VMM::Paging::MapUserIn(proc->pml4Phys, physAddr, userVa + i * 0x1000);
+        }
+
+        proc->heapNext += size;
+        return userVa;
+    }
+
+    static void Sys_Free(uint64_t) {
+        // TODO No-op for now (pages leak)
+    }
+};