Fix LIKE predicates wildcard escaping for SQLite and other non-MySQL/PostgreSQL databases

[Copilot]

Problem

Ransack's LIKE-based predicates (*_cont, *_not_cont, *_start, *_end, etc.) were not properly escaping wildcard characters (%, _, \) in SQLite and other non-MySQL/PostgreSQL databases. This caused unintended matches when search values contained these special characters.

For example, searching for %_ would match any record due to the wildcards being treated as SQL pattern characters instead of literal characters:

# Before fix - matches all records in SQLite
Product.ransack(name_cont: '%_').result
# Generated SQL: WHERE "products"."name" LIKE '%%_%'

Solution

This PR implements consistent wildcard escaping across all database adapters by:

1. Replacing adapter-specific escaping logic with ActiveRecord::Base.sanitize_sql_like in the escape_wildcards method
2. Adding automatic ESCAPE clause detection to include ESCAPE '\' when escaped wildcards are present in LIKE predicates
3. Updating tests to expect proper escaping behavior for all database adapters

Changes

Core Implementation

• lib/ransack/constants.rb: Updated escape_wildcards to use Rails' built-in sanitize_sql_like method
• lib/ransack/nodes/condition.rb: Enhanced format_predicate to automatically add ESCAPE clause when needed

Test Updates

• spec/ransack/predicate_spec.rb: Updated test expectations for SQLite to include ESCAPE clauses and added comprehensive wildcard escaping test coverage

After Fix

# Now works correctly - only matches records containing literal '%_'
Product.ransack(name_cont: '%_').result
# Generated SQL: WHERE "products"."name" LIKE '%\%\_%' ESCAPE '\'

Verification

• ✅ All existing tests pass
• ✅ New tests verify proper wildcard character handling
• ✅ Original reproduction case now works correctly
• ✅ No regressions in broader test suite
• ✅ Consistent behavior across MySQL, PostgreSQL, SQLite, and other supported databases

This fix ensures that wildcard characters in search values are treated as literal characters consistently across all database adapters, making Ransack's search behavior predictable and secure.

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Additional instructions:

ensure additional test coverage is added
refactor relevant code around the changes if useful

Fixes #1581

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