test(payloads): add encode/decode roundtrip tests for all payload types

[phsym]

Summary

• Replaces 3 individual roundtrip tests with a single table-driven TestPayloads_Encode_Decode covering all 27 request/response payload pairs
• Every struct field is populated in the test data to ensure full encode/decode path coverage
• Adds a normalizeTimesToUTC reflection helper to handle TTLV decoding time.Time in local timezone vs UTC originals

[Copilot]

Pull request overview

Consolidates payload encode/decode roundtrip testing into a single table-driven test that aims to cover all request/response payload structs, with a reflection helper to normalize time.Time values for stable equality comparisons.

Changes:

• Replaces multiple per-payload roundtrip tests with a single TestPayloads_Encode_Decode table-driven test covering many payload types.
• Adds normalizeTimesToUTC reflection helper to convert decoded time.Time fields to UTC before equality checks.
• Expands test fixtures to populate many fields across payload structs to exercise encode/decode paths.

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 3 comments.

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[Copilot]

for i := range v.NumField() does not compile because range cannot be used on an int. Use an index loop (e.g., for i := 0; i < v.NumField(); i++) to iterate over struct fields.

Suggested change

	for i := range v.NumField() {
	if f := v.Field(i); f.CanSet() {
	normalizeTimesToUTC(f)
	}
	}
	case reflect.Slice:
	for i := range v.Len() {
	for i := 0; i < v.NumField(); i++ {
	if f := v.Field(i); f.CanSet() {
	normalizeTimesToUTC(f)
	}
	}
	case reflect.Slice:
	for i := 0; i < v.Len(); i++ {

[Copilot]

for i := range v.Len() does not compile because range cannot be used on an int. Use a standard index loop (e.g., for i := 0; i < v.Len(); i++) to iterate over slice elements.

Suggested change

	for i := range v.NumField() {
	if f := v.Field(i); f.CanSet() {
	normalizeTimesToUTC(f)
	}
	}
	case reflect.Slice:
	for i := range v.Len() {
	for i := 0; i < v.NumField(); i++ {
	if f := v.Field(i); f.CanSet() {
	normalizeTimesToUTC(f)
	}
	}
	case reflect.Slice:
	for i := 0; i < v.Len(); i++ {

[Copilot]

The comment says TTLV decoding yields time.Time in local timezone, but ttlv's binary DateTime decoding uses time.Unix(...) (which returns UTC). Since this test only exercises TTLV encode/decode, the justification for normalizeTimesToUTC appears inaccurate; either update the comment to match the actual behavior or scope/rename the helper to the encoding(s) that return local times.

Suggested change

	// so that reflect.DeepEqual works regardless of timezone differences in TTLV decoding.
	// so that reflect.DeepEqual compares equivalent instants consistently even
	// when time values carry different location information.