Add 62 unit tests covering core functionality

[Copilot]

Expanded test coverage from 18 to 80 tests across previously untested core components.

New Test Coverage

• SchemaObjectNameTests (5 tests) - Name quoting, schema handling, special characters
• DatabaseConnectionTests (10 tests) - View registration, retrieval, IsView checks
• DatabaseViewTests (13 tests) - SQL parsing, CreateOrAlter transformation, syntax validation
• InlinerOptionsTests (5 tests) - Default vs recommended configurations
• InlinerResultTests (13 tests) - Output formatting, metadata, reference tracking
• ErrorHandlingTests (8 tests) - Validation errors, warnings for missing aliases and single-part identifiers
• ComplexScenarioTests (11 tests) - Outer joins, multi-level nesting, GROUP BY, CASE, DISTINCT

All tests follow existing NUnit conventions and use in-memory DatabaseConnection instances to avoid external dependencies.

Original prompt

more unit tests

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