M2: live netfilter data path (pf_test per direction), pfattach bring-up, NET_LOCK reentrancy fix, static pfctl

- pfk_hooks: PRE→PF_IN, LOCAL_OUT/POST→PF_OUT v4+v6; replacement/buffer
  handling with NF_STOLEN + re-injection (documented divergence: re-entry)
- pfk_mod: pf_status_init/pfattach + pfi attach via pfk_if event callback
- pfk_kern: NET_LOCK holder reentrancy (fix deadlock when notifier fires
  under the write lock — observed as full-VM network hang)
- tools: static pfctl link for musl VMs

tools/tests/02_translations.conf

@@ -0,0 +1,23 @@
+# PFLINUX offline parse test 2 — translations, redirections, diversion.
+
+xif = "lo"
+table <ext> const { 127.0.0.1 }
+
+set reassemble yes no-df
+set syncookies adaptive (start 25%, end 12%)
+
+pass in quick on $xif inet proto tcp from any to any port 8080 \
+	rdr-to 127.0.0.1 port 80 sticky-address
+pass out quick on $xif inet proto tcp from 127.0.0.0/8 to any \
+	nat-to <ext> static-port
+pass in quick on $xif inet6 proto tcp from any to any port 8080 \
+	rdr-to ::1
+pass in quick on $xif inet proto tcp from any to any port 1723 \
+	route-to 127.0.0.1
+pass in quick on $xif proto tcp from any to any port 21 \
+	divert-to 127.0.0.1 port 7000
+pass in quick on $xif proto tcp from any to any port 110 divert-packet port 2000
+pass quick on $xif inet proto tcp from 127.0.0.5 to any binat-to 127.0.0.9
+pass in quick on $xif inet proto tcp all af-to inet6 from ::1
+match out quick on $xif inet proto tcp all set (delay 100)
+block drop in quick on $xif inet from urpf-failed to any