style: cargo fmt on today's new code (883/884/886/opus-pin)

The mergemaster gates run rustfmt and rejected 864's merge because
several files I added/touched in master today had not been fmt'd.
Six files affected, mostly trivial line-wrapping nits. Fixes the
formatting gate for the next 864 merge attempt.

server/src/http/mcp/mod.rs

@@ -61,11 +61,7 @@ pub async fn mcp_get_handler() -> Response {
 /// `POST /mcp` — JSON-RPC 2.0 entry point for `initialize`, `tools/list`,
 /// `tools/call`, and `notifications/*`.
 #[handler]
-pub async fn mcp_post_handler(
-    req: &Request,
-    body: Body,
-    ctx: Data<&Arc<AppContext>>,
-) -> Response {
+pub async fn mcp_post_handler(req: &Request, body: Body, ctx: Data<&Arc<AppContext>>) -> Response {
     let content_type = req.header("content-type").unwrap_or("");
     if !content_type.is_empty() && !content_type.contains("application/json") {
         return json_response(JsonRpcResponse::error(