Close three WO-WZ-004 review gaps in the guest db driver:
- toDbValue: nil []string now marshals to DbValue_Null (matching []byte /
json.RawMessage); empty-but-non-nil stays a non-NULL empty text[].
- DbValueFixtures: add edge entries (zero time.Time, negative + very-large
numeric strings, empty text[], and text[] elements forcing encodePgTextArray
quoting/escaping). Covered automatically by the table-driven round-trip and
driver-value tests; new dbvalue_test.go covers the toDbValue nil convention.
- Document that TextArray cannot represent a NULL array element (repeated
string has no per-element NULL) in the fixtures file and docs/wasm-abi.md,
a contract limit the WO-WZ-007 host executor must also honor.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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