Improve heartbeat-run CLI and agent detail UI

Rework heartbeat-run command with better error handling and output
formatting. Improve AgentConfigForm field layout. Add CSS for agent
run timeline. Enhance AgentDetail page with runtime status section.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

cli/src/index.ts

@@ -41,6 +41,7 @@ heartbeat
   .description("Run one agent heartbeat and stream live logs")
   .requiredOption("-a, --agent-id <agentId>", "Agent ID to invoke")
   .option("-c, --config <path>", "Path to config file")
+  .option("--api-base <url>", "Base URL for the Paperclip server API")
   .option(
     "--source <source>",
     "Invocation source (timer | assignment | on_demand | automation)",