chore(bench): cross-platform A/B benchmark tooling, refreshed baseline, dev docs #1

	name: A/B bench smoke (Linux)

	# Proves the cross-platform A/B harness scripts/ab-bench.sh actually RUNS
	# end-to-end on Linux: the re-exec survives the in-script branch switches, the
	# unix mvnw builds each side, and the median/diff is produced. This is a SMOKE
	# test of the script orchestration, NOT a perf gate — the numbers it prints are
	# informational (CI noise). Narrowly triggered (only when the script or this
	# workflow changes, or on demand) so it never burdens unrelated PRs. The coarse
	# perf smoke + weekly benchmark diff live in ci.yml; strict JMH in benchmarks-jmh.yml.

	on:
	workflow_dispatch:
	pull_request:
	paths:
	- 'scripts/ab-bench.sh'
	- '.github/workflows/ab-bench-smoke.yml'

	permissions:
	contents: read

	jobs:
	ab-bench-smoke:
	name: ab-bench.sh smoke (main vs develop)
	runs-on: ubuntu-latest
	timeout-minutes: 25
	env:
	JAVA_TOOL_OPTIONS: -Djava.awt.headless=true

	steps:
	- name: Check out repository (full history for the A/B branch switches)
	uses: actions/checkout@v6
	with:
	fetch-depth: 0

	- name: Set up Temurin JDK 17
	uses: actions/setup-java@v5
	with:
	distribution: temurin
	java-version: '17'
	cache: maven

	- name: Make main + develop available as local branches
	run: git fetch --no-tags origin main:main develop:develop

	- name: A/B smoke (single run; asserts the script runs on Linux, exit 0)
	run: bash scripts/ab-bench.sh -a main -b develop -r 1 --cooldown 0

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