fix: read 200 tail lines to find preview through progress noise

Claude Code emits many progress lines during work, burying the last
assistant text. 5 lines was not enough to reach it.

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

session.go

@@ -188,7 +188,7 @@ func FindSessionForProcess(claudeDir string, proc Process) (string, []JSONLMessa
 	})
 
 	newest := topLevel[0]
-	messages, err := TailReadJSONL(newest, 5)
+	messages, err := TailReadJSONL(newest, 200)
 	if err != nil {
 		return "", nil, err
 	}

state.go

@@ -63,8 +63,8 @@ func DetectState(messages []JSONLMessage, now time.Time) SessionState {
 	return Unknown
 }
 
-// ExtractPreview finds the last assistant text content and returns the first
-// 5 lines, truncated to 300 characters.
+// ExtractPreview finds the last assistant text content and returns
+// the first 5 lines, truncated to 300 characters.
 func ExtractPreview(messages []JSONLMessage) string {
 	for i := len(messages) - 1; i >= 0; i-- {
 		msg := messages[i]