Capture usage of the package per process by ingesting instrumentation
log entry in each process that ingest at least one log.
The ingestion of the instrumentation entry reflects the method used for
ingesting first application log (sync/async).

Fixes #6132

ingest intrumentation log entry with dedicated log ID

fix tests failing due to differences in runtime versions
remove output test from example

keep happy path going left
avoid named return values
remove changes from apiv2 package
reduce code footprint by using structs instead of pointers
initialize "constant" values at start time

replace all context.TODO() with context.Background()

Replace sync.Mutex with sync.Once.
Move code to logging package but leave sync artifact in internal to allow testing.
Refactor testing to adapt the changes.