Kill UiMessage variants replaced by state-driven rendering

sync_from_agent reads directly from agent entries, so remove:
- UserInput (pending input shown from MindState.input)
- ToolCall, ToolResult (shown from entries on completion)
- ToolStarted, ToolFinished (replaced by shared active_tools)
- replay_session_to_ui (sync_from_agent handles replay)

-139 lines. Remaining variants are streaming (TextDelta, Reasoning),
status bar state, or ephemeral UI messages (Info, Debug).

Co-Authored-By: Proof of Concept <poc@bcachefs.org>

src/user/ui_channel.rs

@@ -71,54 +71,28 @@ pub struct ContextInfo {
 #[derive(Debug, Clone)]
 #[allow(dead_code)]
 pub enum UiMessage {
-    /// Streaming text delta — routed to conversation or autonomous pane
-    /// based on the current StreamTarget.
+    /// Streaming text delta — routed to conversation or autonomous pane.
     TextDelta(String, StreamTarget),
 
-    /// User's input echoed to conversation pane.
-    UserInput(String),
-
-    /// Tool call header: [tool_name] with args summary.
-    ToolCall {
-        name: String,
-        args_summary: String,
-    },
-
-    /// Full tool result — goes to tools pane.
-    ToolResult {
-        name: String,
-        result: String,
-    },
-
     /// DMN state annotation: [dmn: foraging (3/20)].
     DmnAnnotation(String),
 
     /// Status bar update.
     StatusUpdate(StatusInfo),
 
-    /// Live activity indicator for the status bar — shows what the
-    /// agent is doing right now ("thinking...", "calling: bash", etc).
-    /// Empty string clears the indicator.
+    /// Live activity indicator for the status bar.
     Activity(String),
 
     /// Reasoning/thinking tokens from the model (internal monologue).
-    /// Routed to the autonomous pane so the user can peek at what
-    /// the model is thinking about during long tool chains.
     Reasoning(String),
 
-    /// A tool call started — shown as a live overlay above the status bar.
-    ToolStarted { id: String, name: String, detail: String },
-
-    /// A tool call finished — removes it from the live overlay.
-    ToolFinished { id: String },
-
     /// Debug message (only shown when POC_DEBUG is set).
     Debug(String),
 
     /// Informational message — goes to conversation pane (command output, etc).
     Info(String),
 
-    /// Context loading details — stored for the debug screen (Ctrl+D).
+    /// Context loading details — stored for the debug screen.
     ContextInfoUpdate(ContextInfo),
 
     /// Agent cycle state update — refreshes the F2 agents screen.
@@ -157,78 +131,3 @@ pub fn channel() -> (UiSender, UiReceiver) {
 
 /// Replay a restored session into the TUI panes so the user can see
 /// conversation history immediately on restart. Shows user input,
-/// assistant responses, and brief tool call summaries. Skips the system
-/// prompt, context message, DMN plumbing, and image injection messages.
-pub fn replay_session_to_ui(entries: &[crate::agent::context::ConversationEntry], ui_tx: &UiSender) {
-    use crate::agent::api::types::Role;
-
-    crate::dbglog!("[replay] replaying {} entries to UI", entries.len());
-    for (i, e) in entries.iter().enumerate() {
-        let m = e.message();
-        let preview: String = m.content_text().chars().take(60).collect();
-        crate::dbglog!("[replay]   [{}] {:?} mem={} tc={} tcid={:?} {:?}",
-            i, m.role, e.is_memory(), m.tool_calls.as_ref().map_or(0, |t| t.len()),
-            m.tool_call_id.as_deref(), preview);
-    }
-
-    let mut seen_first_user = false;
-    let mut target = StreamTarget::Conversation;
-
-    for entry in entries {
-        if entry.is_memory() { continue; }
-        let msg = entry.message();
-        match msg.role {
-            Role::System => {}
-            Role::User => {
-                if !seen_first_user {
-                    seen_first_user = true;
-                    continue;
-                }
-                let text = msg.content_text();
-                if text.starts_with("Your context was just compacted")
-                    || text.starts_with("Your context was just rebuilt")
-                    || text.starts_with("[Earlier in this conversation")
-                    || text.starts_with("Here is the image")
-                    || text.contains("[image aged out")
-                {
-                    continue;
-                }
-                if text.starts_with("[dmn]") {
-                    target = StreamTarget::Autonomous;
-                    let first_line = text.lines().next().unwrap_or("[dmn]");
-                    let _ = ui_tx.send(UiMessage::DmnAnnotation(first_line.to_string()));
-                } else {
-                    target = StreamTarget::Conversation;
-                    let _ = ui_tx.send(UiMessage::UserInput(text.to_string()));
-                }
-            }
-            Role::Assistant => {
-                if let Some(ref calls) = msg.tool_calls {
-                    for call in calls {
-                        let _ = ui_tx.send(UiMessage::ToolCall {
-                            name: call.function.name.clone(),
-                            args_summary: String::new(),
-                        });
-                    }
-                }
-                let text = msg.content_text();
-                if !text.is_empty() {
-                    let _ = ui_tx.send(UiMessage::TextDelta(format!("{}\n", text), target));
-                }
-            }
-            Role::Tool => {
-                let text = msg.content_text();
-                let preview: String = text.lines().take(3).collect::<Vec<_>>().join("\n");
-                let truncated = if text.lines().count() > 3 {
-                    format!("{}...", preview)
-                } else {
-                    preview
-                };
-                let _ = ui_tx.send(UiMessage::ToolResult {
-                    name: String::new(),
-                    result: truncated,
-                });
-            }
-        }
-    }
-}