Results 14 issues of Keery Nie

### Summary A small PR for adding a null handling code for the `multiValueHeaders` field. Also contains a small refactor to put `isBase64Encode` check into the validate function to keep...

plugins/aws-lambda
size/M
cherry-pick kong-ee

### Summary Adds several metrics and the ability to export them for kong cache instances. ### Checklist - [ ] The Pull Request has tests - [ ] A changelog...

size/M
cherry-pick kong-ee

### Summary This PR makes the `cert` field of the `ca_certificates` entity referenceable. The `ca_certificates` entity has a `cert_digest` field which is calculated by transformation `on_write` functions. For referenced CA...

core/db
size/L
schema-change-noteworthy
cherry-pick kong-ee

### Summary This PR adjusts the sequence of HTTP fields and their predicates generated inside a traditional compatible route expression, expecting to improve routing matching performance in general situations. Before...

core/router
size/M
cherry-pick kong-ee