feat(mysql): MySQL and MariaDB query dialect, fuzzed on both (#53) - #135

🟢 Confidence 10/10 · safe to merge. The head is a small, tested fix to the shared timestamp check plus a CI job; only the year-0000 leap day escapes both.
_{1 note · tests covered · risk medium}

The last commits make the shared text-timestamp check refuse impossible calendar dates before Date.parse moves them on, pin that with a MySQL test, and add the MySQL/MariaDB CI job. Mergeable; one leap-day edge in the new check.

• realCalendarDate runs before Date.parse in isText and in the Date comparison literal
• mysql.test.ts pins the refused 2023-02-30 and the accepted 2023-02-28
• CI gains a Builder / MySQL 8.4, MariaDB 11.4 job with both services
• The ILIKE refusal now names contains(…, { insensitive: true }) instead of SQLite's rules

Findings

	const [year, month, day] = [Number(date[1]), Number(date[2]), Number(date[3])]
	// `Date.UTC` maps years 00-99 to 19xx, whose leap years are not the year's own.
	const last = new Date(0)
	last.setUTCFullYear(year, month, 0)
	return month >= 1 && month <= 12 && day >= 1 && day <= last.getUTCDate()

_{4dc5d44 · Reply "won't fix" to dismiss a finding, or mention @maple-review-bot to ask about one.}