fix: add --all to cargo fmt in script/test and autoformat codebase

cargo fmt without --all fails with "Failed to find targets" in
workspace repos. This was blocking every story's gates. Also ran
cargo fmt --all to fix all existing formatting issues.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/src/chat/transport/matrix/bot/mentions.rs

@@ -97,9 +97,7 @@ pub fn is_addressed_to_other(body: &str, bot_user_id: &OwnedUserId, bot_name: &s
     // Handles both "@localpart" and "@localpart:homeserver" forms.
     if let Some(rest) = lower.strip_prefix('@') {
         // Extract everything up to the first whitespace character.
-        let word_end = rest
-            .find(|c: char| c.is_whitespace())
-            .unwrap_or(rest.len());
+        let word_end = rest.find(|c: char| c.is_whitespace()).unwrap_or(rest.len());
         let mention = &rest[..word_end]; // e.g. "sally" or "sally:example.com"
 
         // Strip the homeserver part to get just the localpart.