A request's redacted values are put back in its answer

With restore: true on a guardrail policy's input, what redact rewrote as
placeholders comes back in the answer: the model reads "[EMAIL_1]", the
client reads the address it sent. A streamed placeholder split across
events is held until it is whole, and what is held is sent at the end.
The swap runs before the output filter, so the output rules judge the
answer as the client reads it and a placeholder they make of a value the
model invented is never taken for the request's own. The map lives in the
Verdict for the request only; nothing stores, logs or traces it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/reference.md

@@ -320,6 +320,7 @@ rather than repeated.
 | `injection` | `string` | [Rules](#rules) |
 | `deny` | `[]Pattern` | [Rules](#rules) |
 | `max_chars` | `int` | [Rules](#rules) |
+| `restore` | `bool` | [Rules](#rules) |
 | `token_file` | `string` | [SCIM](#scim) |
 | `python` | `string` | [SGLangConfig](#sglangconfig) |
 | `ttft_p99` | `time.Duration` | [SLO](#slo) |
@@ -2769,6 +2770,14 @@ Deny are patterns, matched against the text as a model reads it.
 
 MaxChars refuses text longer than this; zero is no limit.
 
+### `restore`
+
+`bool`
+
+Restore, on input, puts what redact rewrote as placeholders back into
+the answer: the model reads "[EMAIL_1]", the client reads its own
+address. Only the values that request sent, only into its answer.
+
 ## SCIM
 
 ### `token_file`