🔨 zb: Add benchmarks for Message ser/de

[zeenix]

We add separate benchmarks for header and body ser and de. They show the following results when compared to the main branch before #966:

message-ser/small       time:   [3.0693 µs 3.0745 µs 3.0801 µs]
                        change: [-56.616% -55.888% -55.132%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 14 outliers among 100 measurements (14.00%)
  1 (1.00%) low severe
  2 (2.00%) low mild
  4 (4.00%) high mild
  7 (7.00%) high severe
message-ser/big         time:   [2.3432 ms 2.3506 ms 2.3576 ms]
                        change: [-14.648% -13.677% -12.583%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 3 outliers among 100 measurements (3.00%)
  2 (2.00%) high mild
  1 (1.00%) high severe

message-de/header       time:   [164.90 ns 165.33 ns 165.83 ns]
                        change: [-7.5284% -6.5826% -5.1958%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 2 outliers among 100 measurements (2.00%)
  1 (1.00%) high mild
  1 (1.00%) high severe
message-de/body         time:   [3.0474 ms 3.0522 ms 3.0578 ms]
                        change: [-27.527% -26.152% -24.655%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 18 outliers among 100 measurements (18.00%)
  6 (6.00%) low mild
  5 (5.00%) high mild
  7 (7.00%) high severe