fix: strip XML wrapper from replayed user messages (#150)

* fix: strip XML wrapper from replayed user messages

When loading a previous session, user messages were displayed with raw
XML tags (<persona-instructions>, <user-message>, etc.) because the
goose binary stores the full wrapped prompt in its session history.

Add extract_user_message() to parse out just the <user-message> content
before emitting it to the frontend during session replay.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* refactor: move dispatcher tests to separate file to stay under line limit

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* style: apply cargo fmt and trim to file size limit

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: remove blank line to satisfy file size check

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: anchor XML close tag to end of string to avoid truncating user input

Addresses review feedback: if a user's message literally contains
"</user-message>", the previous find()-based approach would truncate.
Now we require the close tag to be at the end of the string, matching
the backend's wrapping format exactly.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/goose2/src-tauri/src/services/acp/manager/dispatcher.rs

@@ -19,6 +19,17 @@ use crate::services::acp::payloads::{
     ToolResultPayload, ToolTitlePayload,
 };
 
+fn extract_user_message(raw: &str) -> &str {
+    const OPEN: &str = "<user-message>\n";
+    const CLOSE: &str = "\n</user-message>";
+    if let Some(start) = raw.find(OPEN) {
+        let inner = start + OPEN.len();
+        if raw[inner..].ends_with(CLOSE) {
+            return &raw[inner..raw.len() - CLOSE.len()];
+        }
+    }
+    raw
+}
 fn model_options_from_select_options(options: &SessionConfigSelectOptions) -> Vec<ModelOption> {
     match options {
         SessionConfigSelectOptions::Ungrouped(values) => values
@@ -386,13 +397,14 @@ impl Client for SessionEventDispatcher {
                         }
                     }
 
+                    let display_text = extract_user_message(&text.text);
                     let message_id = uuid::Uuid::new_v4().to_string();
                     let _ = self.app_handle.emit(
                         "acp:replay_user_message",
                         serde_json::json!({
                             "sessionId": local_session_id,
                             "messageId": message_id,
-                            "text": text.text,
+                            "text": display_text,
                         }),
                     );
                 }
@@ -502,3 +514,6 @@ impl Client for SessionEventDispatcher {
         Ok(())
     }
 }
+#[cfg(test)]
+#[path = "dispatcher_tests.rs"]
+mod tests;

ui/goose2/src-tauri/src/services/acp/manager/dispatcher_tests.rs

@@ -0,0 +1,28 @@
+use super::*;
+
+#[test]
+fn extract_user_message_strips_xml_wrapper() {
+    let wrapped = "<persona-instructions>\nYou are a helpful assistant.\n</persona-instructions>\n\n<user-message>\nhello\n</user-message>";
+    assert_eq!(extract_user_message(wrapped), "hello");
+}
+
+#[test]
+fn extract_user_message_multiline() {
+    let wrapped = "<persona-instructions>\nstuff\n</persona-instructions>\n\n<user-message>\nline one\nline two\n</user-message>";
+    assert_eq!(extract_user_message(wrapped), "line one\nline two");
+}
+
+#[test]
+fn extract_user_message_no_wrapper() {
+    assert_eq!(extract_user_message("plain text"), "plain text");
+}
+
+#[test]
+fn extract_user_message_preserves_inner_delimiter() {
+    // User literally typed "</user-message>" in their message — must not truncate.
+    let wrapped = "<persona-instructions>\nstuff\n</persona-instructions>\n\n<user-message>\ncheck this tag: </user-message> cool right?\n</user-message>";
+    assert_eq!(
+        extract_user_message(wrapped),
+        "check this tag: </user-message> cool right?"
+    );
+}