Summary

• preserve non-numeric pin identifiers as strings instead of coercing to NaN in source port conversion
• treat standalone - tokens as symbols (not numbers) in DSN tokenization so pin labels like - remain valid
• add Smoothie regression test asserting source_port.pin_number is never NaN or null

Reproduction (Issue145-smoothieboard.dsn)

Before:

• source_port count: 1055
• pinNumNan: 456
• pinNumNull: 0

After:

• source_port count: 1055
• pinNumNan: 0
• pinNumNull: 0

Verification

• bun test (full suite)
• bun test tests/repros/repro7-smoothie-board.test.ts

/claim #54