fix(jira,tests): send real datetime to RT/BT date fields, resolve assignee usernames for operators

- RT/BT Start/End Date are genuine Jira "datetime" custom fields (confirmed
  via issue_editmeta), not plain dates. Pushing a bare "YYYY-MM-DD" string
  made Jira default the time-of-day to midnight, so RT Start Date and RT
  End Date ended up showing the same meaningless midnight timestamp instead
  of the actual execution window. Now sends a full ISO datetime.
- The test detail page showed "RT: Unassigned" for the operator who WAS
  correctly assigned, because GET /users/operators (the only source
  AssigneeControl used to resolve an assignee ID into a username) is
  restricted to leads/managers — a plain operator has no other way to
  resolve their own ID. TestOut now resolves and includes the assignee's
  username directly (red/blue tech + reviewer), so the badge no longer
  depends on a permission-gated list the viewer might not have access to.

frontend/src/components/test-detail/AssigneeControl.tsx

@@ -15,6 +15,12 @@ interface Props {
    * techs+leads. "reviewer" = red_reviewer_assignee/blue_reviewer_assignee,
    * picking from leads only — for handing a review off to a peer lead. */
   kind?: "operator" | "reviewer";
+  /** Resolved username from the API. `operators` is only fetched for
+   * leads/managers (GET /users/operators is permission-gated), so a plain
+   * operator viewing their own test can't resolve assigneeId -> name from
+   * that list — this is the fallback so the badge doesn't misreport
+   * "Unassigned" just because the picker data isn't available to them. */
+  assigneeUsername?: string | null;
 }
 
 const SIDE_STYLE = {
@@ -41,10 +47,11 @@ const LABEL_PREFIX: Record<"operator" | "reviewer", Record<"red" | "blue", strin
 /** Lead/manager picker for operator assignment or reviewer hand-off. */
 export default function AssigneeControl({
   side, assigneeId, operators, canEdit, isSaving, onAssign, size = "sm", kind = "operator",
+  assigneeUsername,
 }: Props) {
   const [expanded, setExpanded] = useState(false);
   const current = operators.find((o) => o.id === assigneeId);
-  const label = current ? current.username : "Unassigned";
+  const label = current?.username ?? (assigneeId ? assigneeUsername ?? "Unassigned" : "Unassigned");
   const eligible = operators.filter((o) => ELIGIBLE_ROLES[kind][side].includes(o.role));
   const sideLabel = LABEL_PREFIX[kind][side];
 

frontend/src/components/test-detail/TestDetailHeader.tsx

@@ -559,6 +559,7 @@ export default function TestDetailHeader({
                 side="red"
                 kind="reviewer"
                 assigneeId={test.red_reviewer_assignee}
+                assigneeUsername={test.red_reviewer_assignee_username}
                 operators={operators}
                 canEdit={role === "red_lead" || role === "manager"}
                 isSaving={isAssigningOperator}
@@ -571,6 +572,7 @@ export default function TestDetailHeader({
                 side="blue"
                 kind="reviewer"
                 assigneeId={test.blue_reviewer_assignee}
+                assigneeUsername={test.blue_reviewer_assignee_username}
                 operators={operators}
                 canEdit={role === "blue_lead" || role === "manager"}
                 isSaving={isAssigningOperator}
@@ -581,6 +583,7 @@ export default function TestDetailHeader({
             <AssigneeControl
               side="red"
               assigneeId={test.red_tech_assignee}
+              assigneeUsername={test.red_tech_assignee_username}
               operators={operators}
               canEdit={role === "red_lead" || role === "manager"}
               isSaving={isAssigningOperator}
@@ -590,6 +593,7 @@ export default function TestDetailHeader({
             <AssigneeControl
               side="blue"
               assigneeId={test.blue_tech_assignee}
+              assigneeUsername={test.blue_tech_assignee_username}
               operators={operators}
               canEdit={role === "blue_lead" || role === "manager"}
               isSaving={isAssigningOperator}

frontend/src/types/models.ts

@@ -134,6 +134,8 @@ export interface Test {
   // Assignment fields
   red_tech_assignee: string | null;
   blue_tech_assignee: string | null;
+  red_tech_assignee_username: string | null;
+  blue_tech_assignee_username: string | null;
 
   // Red Team review fields
   red_reviewer_assignee: string | null;
@@ -146,6 +148,8 @@ export interface Test {
   blue_review_by: string | null;
   blue_review_at: string | null;
   blue_review_notes: string | null;
+  red_reviewer_assignee_username: string | null;
+  blue_reviewer_assignee_username: string | null;
   system_gaps: string | null;
 
   // On-hold fields