docs: fix mermaid rendering, drop color fills #5

	name: CI

	on:
	push:
	branches: [main]
	pull_request:
	branches: [main]

	jobs:
	smoke:
	name: Smoke test
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python: ["3.11", "3.12"]
	steps:
	- uses: actions/checkout@v4

	- name: Set up Python ${{ matrix.python }}
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python }}
	cache: pip

	- name: Install
	run: \|
	python -m pip install --upgrade pip
	pip install -e .

	- name: Import check
	run: \|
	python -c "from sqlite_bench import scale_benchmark, before_after, paths, engine, schema, configs, data_generator, monitor, results, report"

	- name: Smoke test before_after (10K rows)
	run: \|
	python -m sqlite_bench.before_after --scales 10K --mode both --output-dir /tmp/smoke

	- name: Smoke test scale_benchmark (3 presets × 5K)
	run: \|
	python -m sqlite_bench.scale_benchmark --scales 5K --configs presets --output-dir /tmp/smoke_scale

	- name: Verify results JSON
	run: \|
	python -c "import json; d=json.load(open('/tmp/smoke/results.json')); assert len(d['results'])>=2"
	python -c "import json; d=json.load(open('/tmp/smoke_scale/results.json')); assert len(d['results'])>=3"

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