feat: split syscalls into files, change max process ceiling

kernel/src/Api/Common.hpp

@@ -0,0 +1,28 @@
+#pragma once
+#include <Sched/Scheduler.hpp>
+
+namespace Zenith {
+    // Find the process that owns the I/O ring buffers for a redirected process.
+    // If proc owns buffers itself (spawned via spawn_redir), returns proc.
+    // If proc inherited redirection (spawned via spawn from a redirected parent),
+    // follows parentPid to find the buffer owner.
+    static Sched::Process* GetRedirTarget(Sched::Process* proc) {
+        if (!proc || !proc->redirected) return nullptr;
+        if (proc->outBuf) return proc;  // owns buffers
+        return Sched::GetProcessByPid(proc->parentPid);
+    }
+
+    static void RingWrite(uint8_t* buf, uint32_t& head, uint32_t /*tail*/, uint32_t size, uint8_t byte) {
+        buf[head] = byte;
+        head = (head + 1) % size;
+    }
+
+    static int RingRead(uint8_t* buf, uint32_t& head, uint32_t& tail, uint32_t size, uint8_t* out, int maxLen) {
+        int count = 0;
+        while (tail != head && count < maxLen) {
+            out[count++] = buf[tail];
+            tail = (tail + 1) % size;
+        }
+        return count;
+    }
+}