fix(pairing): never reject a decrypted NIP-46 payload on shape

RawRequest still dropped real Amber connect requests after aedde8f:
tonight's re-scan (20:11) hit the lenient-params build and the payload
parsed no better. The strict derive rejected non-string ids, missing
ids, object-shaped params, and double-encoded request strings. Replace
the derived Deserialize with a coercion-based one: any valid JSON
deserializes, every scalar becomes text, a JSON-string-wrapped object
is unwrapped, and only truly non-JSON reaches the log path — now
dumping the exact payload plus the real decrypt error (HMAC vs padding
vs wrong key) instead of a generic 'wrong conversation key'.

src/signer/nip46_client.rs

@@ -613,15 +613,21 @@ impl Nip46ClientSigner {
                 eprintln!("[nip46 pairing] could not derive a conversation with this author");
                 continue;
             };
-            let Ok(plain) = nip44_decrypt(&conv, &event.content) else {
+            let plain = match nip44_decrypt(&conv, &event.content) {
-                eprintln!("[nip46 pairing] payload did not decrypt (wrong conversation key)");
+                Ok(p) => p,
-                continue;
+                Err(e) => {
+                    // Surface the REAL failure (HMAC vs wrong key vs invalid
+                    // padding): a malformed NIP-44 frame looks identical to a
+                    // wrong conversation key otherwise.
+                    eprintln!(
+                        "[nip46 pairing] payload did not decrypt: {e} (frame {} chars b64)",
+                        event.content.len()
+                    );
+                    continue;
+                }
             };
             let Ok(request) = serde_json::from_str::<RawRequest>(&plain) else {
-                eprintln!(
+                eprintln!("[nip46 pairing] decrypted payload is not a NIP-46 request: {plain}");
-                    "[nip46 pairing] decrypted payload is not a NIP-46 request (len {})",
-                    plain.len()
-                );
                 continue;
             };
             if request.method != "connect" {
@@ -1855,32 +1861,70 @@ impl Signer for Nip46ClientSigner {
     }
 }
 
-/// Minimal decrypted NIP-46 request.
+/// Minimal decrypted NIP-46 request. Deserialization is maximally lenient:
-#[derive(Debug, Deserialize)]
+/// real signers deviate from the spec'd shape (`id` numeric, `params` an
+/// object instead of an array, raw JSON grants embedded in params), and a
+/// strict parse silently dropped the pairing handshake. Every scalar is
+/// coerced to text instead of rejecting the request.
+#[derive(Debug)]
 struct RawRequest {
     id: String,
     method: String,
-    #[serde(default, deserialize_with = "lenient_params")]
     params: Vec<String>,
 }
 
-/// NIP-46 params are conventionally strings, but real signers embed raw JSON
+impl<'de> serde::Deserialize<'de> for RawRequest {
-/// objects (Amber sends its requested_perms grant object as `connect`
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
-/// params[1]). A strict `Vec<String>` would reject the entire request and
+    where
-/// silently drop the handshake, so non-string params are coerced to their
+        D: serde::Deserializer<'de>,
-/// JSON text instead.
+    {
-fn lenient_params<'de, D>(deserializer: D) -> Result<Vec<String>, D::Error>
+        fn to_text(v: &serde_json::Value) -> String {
-where
+            match v {
-    D: serde::Deserializer<'de>,
+                serde_json::Value::String(s) => s.clone(),
-{
+                other => other.to_string(),
-    let values: Vec<serde_json::Value> = Vec::deserialize(deserializer)?;
+            }
-    Ok(values
+        }
-        .into_iter()
+        let value = serde_json::Value::deserialize(deserializer)?;
-        .map(|v| match v {
+        let mut obj = match value {
-            serde_json::Value::String(s) => s,
+            serde_json::Value::Object(map) => map,
-            other => other.to_string(),
+            // Double-encoded payload: a JSON string wrapping the request
-        })
+            // object. Unwrap one level and retry.
-        .collect())
+            serde_json::Value::String(ref s) => {
+                match serde_json::from_str::<serde_json::Value>(s) {
+                    Ok(serde_json::Value::Object(map)) => map,
+                    _ => {
+                        return Ok(RawRequest {
+                            id: String::new(),
+                            method: String::new(),
+                            params: vec![s.clone()],
+                        });
+                    }
+                }
+            }
+            // Any other non-object is not a JSON-RPC request; surface it as
+            // an empty method (the caller logs and ignores it) rather than
+            // failing, so the raw text still reaches the diagnostic log.
+            other => {
+                return Ok(RawRequest {
+                    id: String::new(),
+                    method: String::new(),
+                    params: vec![to_text(&other)],
+                });
+            }
+        };
+        let id = obj.remove("id").map(|v| to_text(&v)).unwrap_or_default();
+        let method = obj
+            .remove("method")
+            .map(|v| to_text(&v))
+            .unwrap_or_default();
+        let params = match obj.remove("params") {
+            Some(serde_json::Value::Array(arr)) => arr.iter().map(to_text).collect(),
+            Some(serde_json::Value::Null) | None => Vec::new(),
+            // `params` shaped as an object: treat it as a single param.
+            Some(other) => vec![to_text(&other)],
+        };
+        Ok(RawRequest { id, method, params })
+    }
 }
 
 fn response_ok(id: &str, result: String) -> String {
@@ -1976,6 +2020,64 @@ mod raw_request_tests {
         );
     }
 
+    #[test]
+    fn coerces_numeric_ids() {
+        // Some signers use numeric request ids; a strict String id used to
+        // reject the whole request and silently drop the handshake.
+        let req: RawRequest =
+            serde_json::from_str(r#"{"id":42,"method":"connect","params":[]}"#).unwrap();
+        assert_eq!(req.id, "42");
+        let req: RawRequest =
+            serde_json::from_str(r#"{"id":1789267093,"method":"connect","params":["aa","bb"]}"#)
+                .unwrap();
+        assert_eq!(req.id, "1789267093");
+        assert_eq!(req.method, "connect");
+    }
+
+    #[test]
+    fn missing_id_defaults_to_empty() {
+        let req: RawRequest = serde_json::from_str(r#"{"method":"connect"}"#).unwrap();
+        assert_eq!(req.id, "");
+        assert_eq!(req.method, "connect");
+    }
+
+    #[test]
+    fn unwraps_double_encoded_request() {
+        // A signer that JSON-stringifies the whole request object.
+        let inner = r#"{"id":"9","method":"connect","params":["aa"]}"#;
+        let raw = serde_json::Value::String(inner.to_string()).to_string();
+        let req: RawRequest = serde_json::from_str(&raw).expect("must parse");
+        assert_eq!(req.id, "9");
+        assert_eq!(req.method, "connect");
+        assert_eq!(req.params, vec!["aa".to_string()]);
+    }
+
+    #[test]
+    fn accepts_object_shaped_params() {
+        // `params` given as a bare object rather than an array.
+        let req: RawRequest =
+            serde_json::from_str(r#"{"id":"x","method":"connect","params":{"sign_event":[0]}}"#)
+                .expect("must parse");
+        assert_eq!(req.params.len(), 1);
+        assert!(req.params[0].starts_with('{'));
+    }
+
+    #[test]
+    fn never_fails_on_valid_json() {
+        // Whatever a signer sends that is valid JSON must deserialize; the
+        // worst case is an empty method the caller logs and ignores.
+        for raw in [
+            r#"[1,2,3]"#,
+            r#""just a string""#,
+            r#"42"#,
+            r#"null"#,
+            r#"{"no":"fields"}"#,
+        ] {
+            let req: RawRequest = serde_json::from_str(raw).expect("must not fail");
+            assert!(raw.contains("fields") || req.method.is_empty() || req.method == "connect");
+        }
+    }
+
     #[test]
     fn parses_string_params_unchanged() {
         let req: RawRequest =