copy the issue in the conversion

still investigating.

Problem I'm seeing:
- objects are mutated out from under me by Replicache. Object with ID 1 gets mutated to Object with ID 2 and vice-versa.

Potential causes:
- my cvr updates
- replicache upgrade

client/src/issue/issue.ts

@@ -38,7 +38,9 @@ export function issueFromKeyAndValue(
   _key: string,
   value: ReadonlyJSONValue,
 ): Issue {
-  return issueSchema.parse(value);
+  return {
+    ...issueSchema.parse(value),
+  };
 }
 
 export const COMMENT_KEY_PREFIX = `comment/`;

client/src/reducer.ts

@@ -152,6 +152,7 @@ function diffReducer(state: State, diff: Diff): State {
       newFilteredIssues.splice(idx, 0, newIssue);
     }
   }
+
   function del(key: string, oldValue: ReadonlyJSONValue) {
     const oldIssue = issueFromKeyAndValue(key, oldValue);
     const index = sortedIndexBy(newFilteredIssues, oldIssue, orderIteratee);
@@ -163,6 +164,7 @@ function diffReducer(state: State, diff: Diff): State {
       newFilteredIssues.splice(index, 1);
     }
   }
+
   for (const diffOp of diff) {
     switch (diffOp.op) {
       case 'add': {