fix: Apply cargo fmt formatting fixes

Resolves CI formatting check failures by removing trailing whitespace
and excess blank lines in ir_gen_expressions.rs and ir_generator.rs.
Also syncs Cargo.lock to version 2.16.0.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: skeptomai

Cargo.lock

@@ -947,7 +947,7 @@ impl super::IrGenerator {
                         return match source {
                             // Arrays removed - no variables are arrays anymore
                             VariableSource::ObjectTreeRoot(_) => false, // Contents result - NOT an array
-                            VariableSource::Scalar(_) => false,         // Scalar value - NOT an array
+                            VariableSource::Scalar(_) => false, // Scalar value - NOT an array
                         };
                     }
                 }

src/grue_compiler/ir_gen_expressions.rs

@@ -491,9 +491,6 @@ impl IrGenerator {
         Ok(ir_block)
     }
 
-
-
-
     /// Testing method to expose room_objects mapping for integration tests
     #[cfg(test)]
     pub fn get_room_objects(&self) -> &IndexMap<String, Vec<RoomObjectInfo>> {