Snowflake: preserve reluctant MATCH_RECOGNIZE quantifiers

[osipovartem]

What does this PR do?

Preserves the reluctant modifier on Snowflake/SQL MATCH_RECOGNIZE quantifiers. Previously, A*? was represented as (A*)?, changing a reluctant zero-or-more quantifier into a nested optional repetition.

The AST now represents this as Repetition(A, Reluctant(ZeroOrMore)). Existing Repetition(pattern, quantifier) construction remains unchanged, while the added Reluctant quantifier wrapper also covers +?, ??, and range forms such as {2,4}?. Stacked quantifiers that are not the single reluctant suffix are rejected.

Reference

Snowflake documents the reluctant suffix, its non-greedy semantics, and the supported quantifier forms in the MATCH_RECOGNIZE pattern syntax.

Tests

• cargo +1.95.0 test --offline --all-features match_recognize (2 passed)
• cargo +1.95.0 test --offline --all-features
• cargo +1.95.0 fmt --all -- --check
• Upstream stable, beta, nightly, no-std, lint, docs, codestyle, benchmark-lint, RAT, and license checks pass