feat(microkernel): implement pure microkernel architecture with vfs_server, net_server, and procmgr

- Added vfs_server in Ring 3 (Endpoint 5) managing unified VFS tree (/, /bin, /etc, /proc, /dev, /tmp)
- Added net_server in Ring 3 (Endpoint 6) owning RTL8139 hardware NIC, DHCP, DNS, and TCP/IPv4 stack
- Refactored procmgr in Ring 3 (Endpoint 4) to handle userspace process spawning via PROC_OP_SPAWN
- Added primitive microkernel syscalls in Ring 0: SYS_TASK_CREATE (29), SYS_TASK_MAP_PAGE (30), SYS_TASK_START (31)
- Updated shell (sh) and desktop GUI (gui_server) to delegate process management and I/O to Ring 3 daemons
- Expanded boot pipeline to orchestrate 7 concurrent Ring 3 servers across dedicated SMP CPU cores

include/abi/net.h

@@ -16,6 +16,12 @@ extern "C" {
 #define ICMP_ECHO_REPLY   0
 #define ICMP_ECHO_REQUEST 8
 
+/* NET_ENDPOINT (6) IPC Opcodes */
+#define NET_OP_GET_CONFIG 1
+#define NET_OP_PING       2
+#define NET_OP_DNS        3
+#define NET_OP_DHCP       4
+
 #pragma pack(push, 1)
 
 typedef struct {

include/abi/syscalls.h

@@ -31,6 +31,21 @@
 #define SYS_NOTIFY_RECV     26  /* Poll pending desktop notifications non-blockingly */
 #define SYS_MODULE_EXEC     27  /* Find and execute boot module by name (.opc or .elf) */
 #define SYS_MODULE_LIST     28  /* List available boot modules in memory */
+#define SYS_TASK_CREATE     29  /* Allocate new user PML4 & thread structure: (name, name_len) -> tid */
+#define SYS_TASK_MAP_PAGE   30  /* Map page into target task: (target_tid, vaddr, src_buf, flags) -> status */
+#define SYS_TASK_START      31  /* Activate thread: (target_tid, entry_rip, user_rsp) -> status */
+
+/* Standard Ring 3 Service Endpoints */
+#define UART_SERVICE_ENDPOINT 2
+#define PROCMGR_ENDPOINT      4
+#define VFS_ENDPOINT          5
+#define NET_ENDPOINT          6
+
+/* PROCMGR_ENDPOINT (4) IPC Opcodes */
+#define PROC_OP_LIST    1
+#define PROC_OP_KILL    2
+#define PROC_OP_SPAWN   3
+#define PROC_OP_STAT    4
 
 /* POSIX Process Signals */
 #define SIGHUP   1
@@ -249,6 +264,33 @@ static inline int sys_module_list(char *out_buf, size_t max_len) {
     return (int)rax;
 }
 
+static inline int64_t sys_task_create(const char *name, size_t name_len) {
+    register uint64_t rax __asm__("rax") = SYS_TASK_CREATE;
+    register uint64_t rdi __asm__("rdi") = (uint64_t)name;
+    register uint64_t rsi __asm__("rsi") = (uint64_t)name_len;
+    __asm__ volatile("syscall" : "+r"(rax) : "r"(rdi), "r"(rsi) : "rcx", "r11", "memory");
+    return (int64_t)rax;
+}
+
+static inline int64_t sys_task_map_page(uint64_t target_tid, uint64_t vaddr, const void *src_buf, uint64_t flags) {
+    register uint64_t rax __asm__("rax") = SYS_TASK_MAP_PAGE;
+    register uint64_t rdi __asm__("rdi") = target_tid;
+    register uint64_t rsi __asm__("rsi") = vaddr;
+    register uint64_t rdx __asm__("rdx") = (uint64_t)src_buf;
+    register uint64_t r8  __asm__("r8")  = flags;
+    __asm__ volatile("syscall" : "+r"(rax) : "r"(rdi), "r"(rsi), "r"(rdx), "r"(r8) : "rcx", "r11", "memory");
+    return (int64_t)rax;
+}
+
+static inline int64_t sys_task_start(uint64_t target_tid, uint64_t entry_rip, uint64_t user_rsp) {
+    register uint64_t rax __asm__("rax") = SYS_TASK_START;
+    register uint64_t rdi __asm__("rdi") = target_tid;
+    register uint64_t rsi __asm__("rsi") = entry_rip;
+    register uint64_t rdx __asm__("rdx") = user_rsp;
+    __asm__ volatile("syscall" : "+r"(rax) : "r"(rdi), "r"(rsi), "r"(rdx) : "rcx", "r11", "memory");
+    return (int64_t)rax;
+}
+
 #ifdef __cplusplus
 }
 #endif

include/abi/vfs.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include "types.h"
+#include "syscalls.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define VFS_OP_STAT       1
+#define VFS_OP_READ_FILE  2
+#define VFS_OP_WRITE_FILE 3
+#define VFS_OP_LIST       4
+
+typedef struct vfs_file_stat {
+    uint32_t size;
+    uint32_t is_dir;
+} vfs_file_stat_t;
+
+#ifdef __cplusplus
+}
+#endif