Validate byte-preserving record fields as base64 strings

docs/roadmap/remediation.md

@@ -1,8 +1,8 @@
 # Publication reconciliation remediation
 
-Status: open. R01–R13 are addressed and individually verified. R14–R17 record
-remaining findings from the subsequent stage-by-stage review of `363f7cd`.
-Address the two handoff defects first, then the classification and format gaps.
+Status: all corrections are implemented and individually verified; final
+assembled verification is pending. R01–R13 retain their completion evidence.
+R14–R17 describe the subsequent stage-by-stage review of `363f7cd` and its fixes.
 
 R01–R13 describe commits `4dff808` through `599ad81`, against planning baseline
 `447b42a`. Their audit evidence and defect descriptions refer to that reviewed
@@ -734,6 +734,12 @@ reaching a substituted endpoint when a rewrite mismatch is detected.
 
 ## R17: Validate the documented version-2 byte-field representation — P3
 
+**Completed:** Known byte fields load through explicit JSON string validation and
+standard base64 decoding. Tests passed for valid/empty strings, numeric arrays,
+other structural types, malformed base64, and retained decoding causes, alongside
+existing partial/unknown-field, version-1, and lossless endpoint regressions.
+Stage 2/8 instructions and the canonical format guide are updated.
+
 **Relevant code:** `internal/publish/record.go:48–59`;
 [private record format](../integrations/publication-records.md#private-attempt-record).
 Affects Stage 2 and its Stage 8 format coverage.