feat: Improve CLI (#5)

* Start working on improved CLI

* Add tool result previews, boxed approval card, and polished help screen

REPL iteration 2: styled /help with grouped sections, box-drawing
approval card with colored params, dim separator before responses,
inline tool output previews via new StatusUpdate::ToolResult variant.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

---------

Co-authored-by: Claude Opus 4.6 <[email protected]>

src/channels/web/mod.rs

@@ -208,6 +208,7 @@ impl Channel for GatewayChannel {
             StatusUpdate::ToolCompleted { name, success } => {
                 SseEvent::ToolCompleted { name, success }
             }
+            StatusUpdate::ToolResult { name, preview } => SseEvent::ToolResult { name, preview },
             StatusUpdate::StreamChunk(content) => SseEvent::StreamChunk { content },
             StatusUpdate::Status(msg) => SseEvent::Status { message: msg },
             StatusUpdate::ApprovalNeeded {

src/channels/web/sse.rs

@@ -75,6 +75,7 @@ impl SseManager {
                     SseEvent::Thinking { .. } => "thinking",
                     SseEvent::ToolStarted { .. } => "tool_started",
                     SseEvent::ToolCompleted { .. } => "tool_completed",
+                    SseEvent::ToolResult { .. } => "tool_result",
                     SseEvent::StreamChunk { .. } => "stream_chunk",
                     SseEvent::Status { .. } => "status",
                     SseEvent::ApprovalNeeded { .. } => "approval_needed",

src/channels/web/types.rs

@@ -78,6 +78,8 @@ pub enum SseEvent {
     ToolStarted { name: String },
     #[serde(rename = "tool_completed")]
     ToolCompleted { name: String, success: bool },
+    #[serde(rename = "tool_result")]
+    ToolResult { name: String, preview: String },
     #[serde(rename = "stream_chunk")]
     StreamChunk { content: String },
     #[serde(rename = "status")]