Fix AI ignoring tool results and page context in follow-ups

Two issues caused the AI to lose context in multi-turn conversations:

1. Page context was a system message buried before 20 conversation
   messages. Now it's injected directly into the user's message so
   the model sees the data right next to the question.

2. Prior tool results were replayed with role="tool", which many
   Ollama models ignore in conversation history. Now they're replayed
   as assistant messages with a [Tool Result] prefix so the model
   reliably reads them.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/Purrse.Api/Services/ChatService.cs

@@ -134,16 +134,6 @@ public class ChatService : IChatService
             Content = string.Format(SystemPromptTemplate, DateTime.UtcNow.ToString("yyyy-MM-dd"))
         });
 
-        // Page context
-        if (!string.IsNullOrEmpty(request.PageContext))
-        {
-            ollamaMessages.Add(new OllamaToolMessage
-            {
-                Role = "system",
-                Content = $"The user is currently viewing: {request.PageContext}"
-            });
-        }
-
         // Last 20 conversation messages
         var recentMessages = conversation.Messages
             .OrderBy(m => m.CreatedAt)
@@ -152,6 +142,18 @@ public class ChatService : IChatService
 
         foreach (var msg in recentMessages)
         {
+            if (msg.Role == "tool")
+            {
+                // Replay tool results as assistant messages so the model reliably sees them.
+                // Many models ignore or mishandle the "tool" role in conversation replay.
+                ollamaMessages.Add(new OllamaToolMessage
+                {
+                    Role = "assistant",
+                    Content = $"[Tool Result]\n{msg.Content}"
+                });
+                continue;
+            }
+
             var ollamaMsg = new OllamaToolMessage { Role = msg.Role, Content = msg.Content };
             if (msg.ToolCallsJson != null)
             {
@@ -163,8 +165,14 @@ public class ChatService : IChatService
         // Check if the conversation already has tool results from prior turns
         var hasExistingToolResults = recentMessages.Any(m => m.Role == "tool");
 
-        // Add current user message
+        // Inject page context directly into the user message so it's adjacent to
-        ollamaMessages.Add(new OllamaToolMessage { Role = "user", Content = request.Message });
+        // the question. Smaller models lose track of data in distant system messages.
+        var userContent = request.Message;
+        if (!string.IsNullOrEmpty(request.PageContext))
+        {
+            userContent = $"{request.Message}\n\n[Current page data]\n{request.PageContext}";
+        }
+        ollamaMessages.Add(new OllamaToolMessage { Role = "user", Content = userContent });
 
         // Build tool definitions
         var tools = BuildToolDefinitions();