chore(fmt): rustfmt drift cleanup across misc crates

Pure formatter output — no semantic changes. Sweeping these into their
own commit so the FIPS integration diff that follows stays scoped to
the actual feature.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

core/archipelago/src/mesh/ratchet.rs

@@ -285,10 +285,7 @@ impl RatchetState {
         if let Some(mut chain_key) = self.chain_key_recv {
             while self.recv_n < until {
                 let (new_chain_key, message_key) = kdf_chain_key(&chain_key)?;
-                let dh_hex = self
-                    .dh_remote_public
-                    .map(hex::encode)
-                    .unwrap_or_default();
+                let dh_hex = self.dh_remote_public.map(hex::encode).unwrap_or_default();
                 self.skipped_keys.insert((dh_hex, self.recv_n), message_key);
                 chain_key = new_chain_key;
                 self.recv_n += 1;

core/archipelago/src/mesh/steganography.rs

@@ -20,8 +20,7 @@ use serde::{Deserialize, Serialize};
 pub const STEGO_MARKER: u8 = 0xAA;
 
 /// Steganography mode — how real payload bytes are disguised on the wire.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
-#[derive(Default)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, Default)]
 pub enum SteganographyMode {
     /// No steganography — standard 0x02 typed envelope.
     #[default]
@@ -34,7 +33,6 @@ pub enum SteganographyMode {
     SensorNetwork,
 }
 
-
 impl SteganographyMode {
     pub fn from_u8(v: u8) -> Option<Self> {
         match v {
@@ -276,13 +274,11 @@ pub fn wire_size(mode: SteganographyMode, payload_len: usize) -> usize {
     match mode {
         SteganographyMode::Normal => payload_len,
         SteganographyMode::WeatherStation => {
-            let blocks =
-                payload_len.div_ceil(WEATHER_REAL_BYTES_PER_BLOCK);
+            let blocks = payload_len.div_ceil(WEATHER_REAL_BYTES_PER_BLOCK);
             header + blocks * WEATHER_WIRE_BYTES_PER_BLOCK
         }
         SteganographyMode::SensorNetwork => {
-            let blocks =
-                payload_len.div_ceil(SENSOR_REAL_BYTES_PER_BLOCK);
+            let blocks = payload_len.div_ceil(SENSOR_REAL_BYTES_PER_BLOCK);
             header + blocks * SENSOR_WIRE_BYTES_PER_BLOCK
         }
     }