Enable: Profile-Guided Optimization (PGO)

[hatoo]

resolve #264

• Added a script build with pgo in justfile
• try BOLT later
• TODO: add to CI

Current state

for server In pgo/server

v0.6.1

oha -z 10s --no-tui -c 900  http://localhost:8888/

Requests/sec: 606825.6121

LTO+PGO+(etc)

just # to build
./target/x86_64-unknown-linux-gnu/release/oha -z 10s --no-tui -c 900  http://localhost:8888

Requests/sec: 684939.1770

It looks noticeably fater