refactor(swap): rename imported .md files to md- prefix for swap mechanism

Restore the canary file naming convention that swap_sources.py expects:
the imported MyST pages now live as docs/<dir>/md-<name>.md alongside
the existing docs/<dir>/<name>.rst, so swap_sources.py --swap can rename
them into place at build time.

- 254 .md files renamed (every page with a matching .rst counterpart)
- 2 MyST-only pages left at their final names (no .rst exists, no swap
  needed): docs/copyright.md, docs/automation/terraform/terraformvyos.md

All 114 stems listed in docs/_swap.txt now have a corresponding
md-<name>.md source file ready to swap in.

🤖 Generated by [robots](https://vyos.io)

1 files changed, 72 insertions, 0 deletions

diff --git a/docs/configuration/protocols/md-arp.md b/docs/configuration/protocols/md-arp.md
new file mode 100644
index 00000000..7d9bf4f9
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+++ b/docs/configuration/protocols/md-arp.md
@@ -0,0 +1,72 @@
+```{eval-rst}
+.. meta::
+   :description: The Address Resolution Protocol (ARP) resolves
+                 network-layer addresses to link-layer MAC addresses.
+   :keywords: arp, network, protocol, mac, address, ipv4, static
+```
+
+(routing_static_arp)=
+
+# ARP
+
+The {abbr}`ARP (Address Resolution Protocol)` resolves IPv4 network layer addresses
+to link layer MAC addresses.
+addresses. This mapping is essential for communication within the Internet
+Protocol suite. ARP was standardized in 1982 by {rfc}`826` (STD 37).
+
+:::{note}
+In Internet Protocol version 6 (IPv6) networks, address resolution is
+performed by the Neighbor Discovery Protocol (NDP).
+:::
+
+Use the following commands to configure or view ARP table entries.
+
+## Configuration
+
+```{eval-rst}
+.. cfgcmd:: set protocols static arp interface <interface> address <host> mac <mac>
+
+   **Configure a static ARP entry on the specified interface.**
+
+   This creates a permanent mapping between an IP address and a MAC address
+   on the specified interface.
+
+   Example:
+
+   .. code-block:: none
+
+      set protocols static arp interface eth0 address 192.0.2.1 mac 01:23:45:67:89:01
+```
+
+## Operation
+
+```{eval-rst}
+.. opcmd:: show protocols static arp
+
+   Show all ARP table entries across all interfaces.
+
+   .. code-block:: none
+
+      vyos@vyos:~$ show protocols static arp
+      Address                  HWtype  HWaddress           Flags Mask     Iface
+      10.1.1.1                 ether   00:53:00:de:23:2e   C              eth1
+      10.1.1.100               ether   00:53:00:de:23:aa   CM             eth1
+```
+
+```{eval-rst}
+.. opcmd:: show protocols static arp interface <interface>
+
+   Show all ARP table entries for the specific interface.
+
+   Example for ``eth1``:
+
+   .. code-block:: none
+
+      vyos@vyos:~$ show protocols static arp interface eth1
+      Address                  HWtype  HWaddress           Flags Mask     Iface
+      10.1.1.1                 ether   00:53:00:de:23:2e   C              eth1
+      10.1.1.100               ether   00:53:00:de:23:aa   CM             eth1
+```
+
+[arp]: https://en.wikipedia.org/wiki/Address_Resolution_Protocol
+