Add badges field to Metadata (#4900)

## Describe your changes

Web apps are currently unable to visually distinguish certain IBC assets
that represent rehypothecated tokens. Aka, Bitcoin from Osmosis or
Nomic. Both of their metadata possess images of the plain Bitcoin logo.

This proto change proposes to add a new field: `badges`. It gives
entities like the [prax
registry](https://github.com/prax-wallet/registry) the ability to add
source chain icons to the metadata of assets. Frontends can then display
these badges [on top
of](penumbra-zone/web#1864 (comment))
the asset icon.

## Issue ticket number and link

penumbra-zone/web#1864
prax-wallet/registry#97

## Checklist before requesting a review

- [x] (not relevant) I have added guiding text to explain how a reviewer
should test these changes.

- [x] If this code contains consensus-breaking changes, I have added the
"consensus-breaking" label. Otherwise, I declare my belief that there
are not consensus-breaking changes, for the following reason:

  > Only a protobuf schema update

crates/core/asset/src/asset/denom_metadata.rs

@@ -39,6 +39,7 @@ pub(super) struct Inner {
     // For now, don't bother with a domain type here,
     // since we don't render images from Rust code.
     images: Vec<pb::AssetImage>,
+    badges: Vec<pb::AssetImage>,
     priority_score: u64,
 
     /// Sorted by priority order.
@@ -65,6 +66,7 @@ impl From<&Inner> for pb::Metadata {
             penumbra_asset_id: Some(inner.id.into()),
             denom_units: inner.units.clone().into_iter().map(|x| x.into()).collect(),
             images: inner.images.clone(),
+            badges: inner.badges.clone(),
             priority_score: inner.priority_score,
         }
     }
@@ -131,6 +133,7 @@ impl TryFrom<pb::Metadata> for Inner {
             name: value.name,
             symbol: value.symbol,
             images: value.images,
+            badges: value.badges,
             priority_score: value.priority_score,
         })
     }
@@ -253,6 +256,7 @@ impl Inner {
             name: String::new(),
             symbol: String::new(),
             images: Vec::new(),
+            badges: Vec::new(),
             priority_score: 0,
         }
     }
@@ -429,13 +433,15 @@ impl Debug for Metadata {
             name,
             symbol,
             priority_score,
+            badges,
         } = inner.as_ref();
 
         f.debug_struct("Metadata")
             .field("id", id)
             .field("base_denom", base_denom)
             .field("description", description)
             .field("images", images)
+            .field("badges", badges)
             .field("priority_score", priority_score)
             .field("units", units)
             .field("display_index", display_index)

crates/proto/src/gen/penumbra.core.asset.v1.rs

@@ -89,6 +89,10 @@ pub struct Metadata {
     /// This is solely for use in client-side registries.
     #[prost(uint64, tag = "1986")]
     pub priority_score: u64,
+    /// Associated icons for asset.
+    /// For ibc assets, usually an image of the source chain.
+    #[prost(message, repeated, tag = "1987")]
+    pub badges: ::prost::alloc::vec::Vec<AssetImage>,
 }
 impl ::prost::Name for Metadata {
     const NAME: &'static str = "Metadata";

crates/proto/src/gen/penumbra.core.asset.v1.serde.rs

@@ -1039,6 +1039,9 @@ impl serde::Serialize for Metadata {
         if self.priority_score != 0 {
             len += 1;
         }
+        if !self.badges.is_empty() {
+            len += 1;
+        }
         let mut struct_ser = serializer.serialize_struct("penumbra.core.asset.v1.Metadata", len)?;
         if !self.description.is_empty() {
             struct_ser.serialize_field("description", &self.description)?;
@@ -1068,6 +1071,9 @@ impl serde::Serialize for Metadata {
             #[allow(clippy::needless_borrow)]
             struct_ser.serialize_field("priorityScore", ToString::to_string(&self.priority_score).as_str())?;
         }
+        if !self.badges.is_empty() {
+            struct_ser.serialize_field("badges", &self.badges)?;
+        }
         struct_ser.end()
     }
 }
@@ -1090,6 +1096,7 @@ impl<'de> serde::Deserialize<'de> for Metadata {
             "images",
             "priority_score",
             "priorityScore",
+            "badges",
         ];
 
         #[allow(clippy::enum_variant_names)]
@@ -1103,6 +1110,7 @@ impl<'de> serde::Deserialize<'de> for Metadata {
             PenumbraAssetId,
             Images,
             PriorityScore,
+            Badges,
             __SkipField__,
         }
         impl<'de> serde::Deserialize<'de> for GeneratedField {
@@ -1134,6 +1142,7 @@ impl<'de> serde::Deserialize<'de> for Metadata {
                             "penumbraAssetId" | "penumbra_asset_id" => Ok(GeneratedField::PenumbraAssetId),
                             "images" => Ok(GeneratedField::Images),
                             "priorityScore" | "priority_score" => Ok(GeneratedField::PriorityScore),
+                            "badges" => Ok(GeneratedField::Badges),
                             _ => Ok(GeneratedField::__SkipField__),
                         }
                     }
@@ -1162,6 +1171,7 @@ impl<'de> serde::Deserialize<'de> for Metadata {
                 let mut penumbra_asset_id__ = None;
                 let mut images__ = None;
                 let mut priority_score__ = None;
+                let mut badges__ = None;
                 while let Some(k) = map_.next_key()? {
                     match k {
                         GeneratedField::Description => {
@@ -1220,6 +1230,12 @@ impl<'de> serde::Deserialize<'de> for Metadata {
                                 Some(map_.next_value::<::pbjson::private::NumberDeserialize<_>>()?.0)
                             ;
                         }
+                        GeneratedField::Badges => {
+                            if badges__.is_some() {
+                                return Err(serde::de::Error::duplicate_field("badges"));
+                            }
+                            badges__ = Some(map_.next_value()?);
+                        }
                         GeneratedField::__SkipField__ => {
                             let _ = map_.next_value::<serde::de::IgnoredAny>()?;
                         }
@@ -1235,6 +1251,7 @@ impl<'de> serde::Deserialize<'de> for Metadata {
                     penumbra_asset_id: penumbra_asset_id__,
                     images: images__.unwrap_or_default(),
                     priority_score: priority_score__.unwrap_or_default(),
+                    badges: badges__.unwrap_or_default(),
                 })
             }
         }

proto/penumbra/penumbra/core/asset/v1/asset.proto

@@ -67,6 +67,10 @@ message Metadata {
   //
   // This is solely for use in client-side registries.
   uint64 priority_score = 1986;
+
+  // Associated icons for asset.
+  // For ibc assets, usually an image of the source chain.
+  repeated AssetImage badges = 1987;
 }
 
 // DenomUnit represents a struct that describes a given denomination unit of the basic token.