style(clippy): clean up the two lints in phase3 new code

QC smoke sweep flagged two clippy -D warnings lints in code this branch
introduced:

- crates/core/src/process_watch.rs — collapsible_if on the meeting-pattern
  match loop, merged the two conditions with &&.
- crates/mcp/src/lib.rs — let-else on the id unwrap that short-circuits a
  notification, switched to ? since handle_message already returns Option.

All other clippy lints under -D warnings (audio/capture, hotkey/linux,
storage/file_storage, diagnostics, the duplicate-detection helpers in
live.rs) predate this branch and are out of scope.

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

crates/mcp/src/lib.rs

@@ -59,9 +59,7 @@ pub async fn handle_message(pool: &SqlitePool, raw: Value) -> Option<JsonRpcResp
     };
 
     // Notifications: no id, no response.
-    let Some(id) = request.id.clone() else {
-        return None;
-    };
+    let id = request.id.clone()?;
 
     let outcome = match request.method.as_str() {
         "initialize" => Ok(initialize_result()),