Move blocker and paused-assignee notices inline with thread

Previously the blocked-issue and assignee-paused banners lived inside
the sticky composer dock, so they floated with the input as the page
scrolled. Render them inline at the end of the message list instead so
they stay with the conversation content, not the floating composer.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

ui/src/components/IssueChatThread.tsx

@@ -2693,6 +2693,12 @@ export function IssueChatThread({
                   return <IssueChatSystemMessage key={message.id} message={message} />;
                 })
               )}
+              {showComposer ? (
+                <div data-testid="issue-chat-thread-notices" className="space-y-2">
+                  <IssueBlockedNotice issueStatus={issueStatus} blockers={unresolvedBlockers} />
+                  <IssueAssigneePausedNotice agent={assignedAgent} />
+                </div>
+              ) : null}
               <div ref={bottomAnchorRef} />
               {showComposer ? (
                 <div
@@ -2711,8 +2717,6 @@ export function IssueChatThread({
             data-testid="issue-chat-composer-dock"
             className="sticky bottom-[calc(env(safe-area-inset-bottom)+20px)] z-20 space-y-2 bg-gradient-to-t from-background via-background/95 to-background/0 pt-6"
           >
-            <IssueBlockedNotice issueStatus={issueStatus} blockers={unresolvedBlockers} />
-            <IssueAssigneePausedNotice agent={assignedAgent} />
             <IssueChatComposer
               ref={composerRef}
               onImageUpload={imageUploadHandler}