chore(config): consolidate mocharc monorepo (#8415)

* chore: remove .mocharc.js generation and update package.json templates to point to root mocharc

* chore: create unified root mocharc.js with parallel workers, update ci test runner memory limits, and remove all duplicate package-level configs

* chore: enable recursive testing in root mocharc

* chore: update generator templates, GHA workflow, baselines, and retryable map test to support unified mocharc.cjs

* chore: rename root mocharc to .cjs, add generic batch test runner under ci/, and lower CI memory limit to 6GB

* chore: add root .mocharc.cjs config to satisfy baseline generator tests

* chore: configure system-test templates and baselines to disable parallel execution

* chore: use generic batch test runner for compute to prevent CI OOM failures

* chore: remove generic batch runner and standardize compute unit test command to parallel mocha

* chore: revert compute package.json test script to standard parallel mocha config

Author: quirogas

ci/run_single_test.sh

@@ -18,7 +18,7 @@ set -e
 
 export REGION_ID='uc'
 export PROJECT_ROOT=$(realpath $(dirname "${BASH_SOURCE[0]}")/..)
-export NODE_OPTIONS=--max_old_space_size=4096
+export NODE_OPTIONS=--max_old_space_size=6144
 
 if [ -z "${BUILD_TYPE}" ]; then
     echo "missing BUILD_TYPE env var"