Take rustfmt's defaults

The code was hand-formatted -- close to rustfmt's output but not it, mostly
in keeping chains and call arguments on one line where the formatter would
break them. That is a per-line decision every future change has to make
again, and reproducing it would mean a config whose only job is to preserve
how the code already looks.

So this is `cargo fmt` at its defaults, with no rustfmt.toml, which is
where the sibling dev-updater checkout already sits: it is clean at the
defaults today, so the two repos now agree on layout without either of them
configuring it.

Formatting only -- no behaviour, no renames, nothing reordered. Verified
after: cargo test (35 pass), cargo clippy --all-targets clean, cargo fmt
--check clean.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017xn8nHw1tw1R6PtiY1eEtw

server/src/session/driver.rs

@@ -26,17 +26,27 @@ pub enum Event {
     /// What the user sent, echoed into the transcript by the manager (not
     /// by drivers) so every device renders the full conversation from the
     /// one stream.
-    UserMessage { text: String },
+    UserMessage {
+        text: String,
+    },
     /// Streaming assistant text; the phone renders the concatenation as
     /// markdown.
-    AssistantText { delta: String },
+    AssistantText {
+        delta: String,
+    },
     ToolStart {
         id: String,
         tool: String,
         input: serde_json::Value,
     },
-    ToolUpdate { id: String, output: String },
-    ToolEnd { id: String, output: String },
+    ToolUpdate {
+        id: String,
+        output: String,
+    },
+    ToolEnd {
+        id: String,
+        output: String,
+    },
     /// An image the session produced or was sent, saved under the session
     /// dir and referenced by id; the phone fetches it by URL.
     Image {
@@ -53,11 +63,20 @@ pub enum Event {
     /// The manager's record of a question being answered, so a rendered
     /// question card resolves on every device, not just the one that
     /// answered it.
-    Answered { id: String, answer: String },
-    Status { state: SessionStatus },
+    Answered {
+        id: String,
+        answer: String,
+    },
+    Status {
+        state: SessionStatus,
+    },
     /// Per-turn token counts, where the dialect reports them.
-    UsageDelta { tokens: u64 },
-    Error { message: String },
+    UsageDelta {
+        tokens: u64,
+    },
+    Error {
+        message: String,
+    },
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]