1.0Performance: Add L1 aggregation flush period, which reduces the CPU load and helps young GC.

2. Replace do not direct send after the first aggregation to reduce the network #6400.

3. Enhance the DataCarrier to notify the consumer in no enqueue event in short term.

4. L1 aggregation flush period still works even no further metrics generated, powered by <3>

5. Fix gRPC remote client OOM. The concurrency control mechanism failed.

* Optimize IDs reading in the persistent worker.

There are a lot of calls to `Metrics.id()` and `ISource.getEntityId`, which calculates the id by manipulating strings in every single call, producing many garbage objects.

In this patch, I cache the id and only calculate the id if it's requested for the first time.

The possible metrics names are relatively fixed in an OAP run, we previously always escape the metrics names, building a new regex Pattern from scratch, which is cpu-consuming.

In this patch, I cache the escaped metrics names, and if it missed, use a pre-compiled regex Pattern to escape the metrics name.

This patch also replace string concatenation `+` with `StringBuilder` in generated classes, which won't get optimized by Java compiler

This may reduce 1~1.5 vCPU under 20K RPS environment.

These fields in `stateMap` metadata are not used by `metadata-service-mapping.yaml` now and there is low possibility that they may be used in real case, but, they cost a lot to deserialize, so we remove them to improve performance

From what I've tested, the analyzer can process 250k ALS logs before trimming the fields and can process 420k ALS logs after trimming the fields

Perf: optimize Envoy ALS analyzer performance in high traffic load scenario (reduce ~1cpu in ~10k RPS) (#7182)

chore: set openAPI grouping CoreModuleConfig default value consistent with application.yaml, add re-benchmark result (#7176)

* OAL supports generating metrics from events

* Add new dashboard for event metrics

* Add some docs for event metrics