profiler: Fill in the profiler state functions (#1226)

* profiler: Fill in the profiler state functions

This patch is a follow-up to #1213

It fills in the profiler state implementation, so that it can be
usable from the whamm monitor.

The most notable change that is not described in the original issue,
is the profile result encoding format, described in the `format.rs` module.

* Review comments

v8.1.1 (#1168)

Update versions, in preparation for a release (#1155)

cli - v8.0.0, codegen - v3.0.0, plugin-api - v5.0.0, javy - v6.0.0 (#…

…1077)

v5.1.0 of javy, v4.1.0 of javy-plugin-api, v7.0.1 of the Javy CLI (#1026

)

v7.0.0 (#1019)

Bump crate versions (#999)

v5.0.4 (#948)

v5.0.3 (#917)

v5.0.2 (#902)