style: apply current rustfmt to the tree

A newer rustfmt wraps over-long match arms and call expressions that the
version main was last formatted with left on one line. Pure formatting,
no semantic change — split out so the friends-list feature commits stay
focused on real changes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/common/config.rs

@@ -84,7 +84,6 @@ pub enum BandwidthStatus {
     Failed,
 }
 
-
 fn default_status() -> BandwidthStatus {
     BandwidthStatus::Unmeasured
 }
@@ -116,11 +115,9 @@ pub fn save(cfg: &Config) -> Result<()> {
     let parent = path
         .parent()
         .context("config path has no parent directory")?;
-    fs::create_dir_all(parent)
-        .with_context(|| format!("failed to create {}", parent.display()))?;
+    fs::create_dir_all(parent).with_context(|| format!("failed to create {}", parent.display()))?;
 
-    let serialized =
-        toml::to_string_pretty(cfg).context("failed to serialize config to TOML")?;
+    let serialized = toml::to_string_pretty(cfg).context("failed to serialize config to TOML")?;
 
     let tmp = parent.join(format!(".config.toml.tmp.{}", std::process::id()));
     {