Support enhanced display of interrupted tool calls

[brainlid]

Summary

• Display interrupted tool calls with distinct visual treatment (✋ icon, amber "INTERRUPTED" badge, interrupt data panel) instead of the default success styling
• Show interrupt data details in a highlighted code block beneath interrupted tool results
• Format interrupt summaries in the event timeline, distinguishing direct HITL interrupts from sub-agent HITL interrupts
• Bump sagents dependency to ~> 0.3.0 (and langchain to 0.6.1 via transitive dep)

Changes

Message Components (message_components.ex)

• tool_result_item/1 now checks is_interrupt and interrupt_data fields on tool results
• Interrupted results render with ✋ icon and an amber "INTERRUPTED" status badge
• Interrupt data is displayed in a collapsible highlighted Elixir code block

Agent List Live (agent_list_live.ex)

• Added format_event_data/1 clause for {:status_changed, :interrupted, data} events
• Tool result status indicators now show ✋ for interrupts (alongside existing ✓/✗)
• Added format_interrupt_summary/1 with clauses for sub-agent HITL and direct HITL interrupt data

Layouts (layouts.ex)

• Added .status-interrupted CSS (amber background, dark amber text)
• Added .tool-result-interrupt-data styling (amber border, light amber background)

Dependencies

• sagents bumped from ~> 0.2.1 to ~> 0.3.0

Test plan

• Verify interrupted tool results display with ✋ icon and INTERRUPTED badge
• Verify interrupt data renders in highlighted code block
• Verify event timeline shows interrupt summaries for both direct and sub-agent HITL
• Verify non-interrupted tool results are unaffected (still show ✅)