feat: add Query Builder whereBetween methods

[memleakd]

Description

This PR proposes adding whereBetween(), orWhereBetween(), whereNotBetween(), and orWhereNotBetween() to the Query Builder.

BETWEEN and NOT BETWEEN conditions are common when filtering by date ranges, numeric ranges, prices, scores, and other lower/upper bound values. Today users can already write these conditions manually with where(), but that usually means writing the BETWEEN ... AND ... expression as a raw condition.

This adds a small Query Builder-native option:

$builder->whereBetween('created_at', ['2026-01-01', '2026-01-31']);

This keeps range conditions readable while still using Query Builder binds for the lower and upper values and normal identifier protection for the field name.

The range array must contain exactly two values: the lower and upper bounds. BETWEEN is inclusive, matching SQL behavior.

The API follows the existing Query Builder style used by methods like whereIn(): field name first, values second, optional $escape third. Users who need a more complex SQL expression can still use where() with RawSql.

Changes

• Added whereBetween() and orWhereBetween().
• Added whereNotBetween() and orWhereNotBetween().
• Added Model PHPDoc forwarding entries.
• Added user guide docs, class reference entries, and changelog entry.
• Added tests for normal, OR, NOT BETWEEN, grouped conditions, bind handling, escape: false, table prefixes, aliases added after the condition, and invalid inputs.

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value (without duplication)
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide