[Feature]: Advanced WHERE conditions (gt, lt, like, in, between)

**Problem Statement:**
Current query methods only support exact equality matching. Applications need complex conditions like range queries, pattern matching, and list filtering.

**Proposed Solution:**
Extend query builder with fluent interface:

```typescript
// Current: only exact matches
User.find({ age: 25 });

// Proposed: rich query conditions
User.query()
.where('age').greaterThan(18)
.where('age').lessThanOrEqual(65)
.where('name').like('%john%')
.where('status').in(['active', 'pending'])
.where('createdAt').between(startDate, endDate)
.orderBy('name', 'ASC')
.limit(10)
.offset(20)
.execute();
```

**Operators to Support:**
- Comparison: gt, gte, lt, lte, ne (not equal)
- Pattern: like, ilike (case-insensitive)
- Lists: in, notIn
- Range: between, notBetween
- Null checks: isNull, isNotNull
- Logic: and, or, not

The issue names no files or tests; start by locating the existing query methods and query builder, then compare them with the User.find({ age: 25 }) example. Done means the fluent interface supports the listed comparison, pattern, list, range, null, and logic conditions, plus orderBy, limit, offset, and execute.

Written by the indexing model from the issue text.