M1 progress: engine port compiles except pf.c; AF_DIVERT socket family; ifq framework

- compat layer extended through the full BSD API surface pf_ioctl/pf_lb/
  pf_if/pf_norm/pf_table/pf_ruleset/radix/md5/sha2 need (all compile):
  cpumem/counters model, ifaddr/ifg groups, cred view, endian+in6 names,
  NAT46/64, SipHash24, mbuf_list, frag6 helpers, ip6 forward/checksum,
  tcp options/FSM names, taskqueue & sysctl shims (documented in
  docs/porting-notes.md)
- pfsrc/divert_sock.c: real BSD divert(4) as runtime-registered PF_DIVERT=32
  socket family inside the module (sock_register; NPROTO=AF_MAX=45 -> zero
  core patches); divert_packet/divert6_packet wired for pf.c
- compat/pfk_ifq.c: OpenBSD 8.0 ifq framework with priq back end; hfsc and
  fq_codel aliases pending M5 (recorded in feature matrix as pending)
- design + plan updated for the divert decision (user-requested)
- stage-port.sh: single deterministic rename program for headers and .c

module/pfsrc/pfk_mod.c

@@ -1,86 +0,0 @@
-/*
- * PF-on-Linux: pfk module core — load/exit, /dev/pf misc device,
- * NET_LOCK bring-up, staged upstream bring-up hooks. (ISC 2026)
- */
-#include <pfk.h>
-#include <pfk_api.h>
-#include <net/pfvar.h>
-#include <net/pfvar_priv.h>
-
-extern void pfk_mbuf_exit(void);
-extern int pfk_if_init(void);
-extern void pfk_if_exit(void);
-
-static int pfk_open(struct inode *inode, struct file *filp)
-{
-	if (filp->f_mode & FMODE_WRITE)
-		return capable(CAP_NET_ADMIN) ? 0 : -EPERM;
-	return 0;
-}
-
-static long pfk_ioctl_io(struct file *filp, unsigned int cmd,
-	unsigned long arg)
-{
-	if (!capable(CAP_NET_ADMIN))
-		return -EPERM;
-	return pfk_ioctl(filp, cmd, arg);
-}
-
-static const struct file_operations pfk_fops = {
-	.owner		= THIS_MODULE,
-	.open		= pfk_open,
-	.unlocked_ioctl	= pfk_ioctl_io,
-	.compat_ioctl	= compat_ptr_ioctl,
-};
-
-static struct miscdevice pfk_dev = {
-	.minor	= MISC_DYNAMIC_MINOR,
-	.name	= "pf",
-	.fops	= &pfk_fops,
-	.mode	= 0600,
-};
-
-static int __init pfk_init(void)
-{
-	int err;
-
-	pfk_net_lock_init();
-	err = pfk_mbuf_init();
-	if (err)
-		return err;
-	err = pfk_if_init();
-	if (err)
-		goto err_mbuf;
-	err = pfk_hooks_register();
-	if (err)
-		goto err_if;
-	err = misc_register(&pfk_dev);
-	if (err)
-		goto err_hooks;
-	pr_info("pfk: PF-on-Linux engine loaded (OpenBSD 8.0 base)\n");
-	return 0;
-err_hooks:
-	pfk_hooks_unregister();
-err_if:
-	pfk_if_exit();
-err_mbuf:
-	pfk_mbuf_exit();
-	return err;
-}
-
-static void __exit pfk_exit(void)
-{
-	misc_deregister(&pfk_dev);
-	pfk_hooks_unregister();
-	pfk_if_exit();
-	pfk_mbuf_exit();
-	pr_info("pfk: unloaded\n");
-}
-
-module_init(pfk_init);
-module_exit(pfk_exit);
-MODULE_LICENSE("Dual MIT/GPL");	/* ISC/BSD code; Dual MIT/GPL is the kernel-
-				 * recognised tag for permissive BSD-licensed
-				 * modules linking GPL exports (see LICENSE). */
-MODULE_DESCRIPTION("PF packet filter (ported from OpenBSD 8.0) for Linux");
-MODULE_AUTHOR("PF-on-Linux contributors");