fix: implement native Ollama thinking semantics

Model Ollama chat thinking separately from final content, preserve it only across assistant tool-call continuation, and keep private reasoning out of user results, session context, and logs.

Accept native boolean and low/medium/high/max think values, normalize YAML booleans, and serialize explicit overrides using the native top-level chat field.

Stop forcing think=false for structured planning, skill selection, and context summaries; corrected retries now retain the configured thinking mode.

Update the specification, design, audit report, and requirement traceability for OLL-14.

Add request/response, configuration, observability, retry, and tool-continuation coverage. Verified with 92 passing Agent.Core tests and a deepseek-v4-flash:cloud think:true MCP operational run.

1 files changed, 3 insertions, 2 deletions

diff --git a/src/Agent.Core/Ollama/OllamaClient.cs b/src/Agent.Core/Ollama/OllamaClient.cs
index 428bca9..fea5dfb 100644
--- a/src/Agent.Core/Ollama/OllamaClient.cs
+++ b/src/Agent.Core/Ollama/OllamaClient.cs
@@ -57,7 +57,7 @@ public sealed class OllamaClient : IOllamaClient
             Model = _settings.Model,
             Messages = messages,
             Stream = false,
-            Think = thinkOverride ?? _settings.Think,
+            Think = thinkOverride is null ? _settings.Think : thinkOverride.Value,
             KeepAlive = _settings.KeepAlive,
             Options = options,
             Tools = tools?.Select(static tool => new OllamaToolDefinition("function", new OllamaFunctionDefinition(tool.Name, tool.Description, tool.Parameters))).ToArray(),
@@ -85,7 +85,8 @@ public sealed class OllamaClient : IOllamaClient
                     ?? throw new OllamaException("Ollama returned an empty response.", false);
                 if (!string.IsNullOrWhiteSpace(result.Error)) throw new OllamaException(result.Error, false);
                 if (result.Message is null) throw new OllamaException("Ollama response has no message.", false);
-                return new OllamaResult(result.Message.Content, result.PromptEvalCount, result.EvalCount, result.Message.ToolCalls ?? [], result.PromptEvalCount);
+                return new OllamaResult(result.Message.Content, result.PromptEvalCount, result.EvalCount,
+                    result.Message.ToolCalls ?? [], result.PromptEvalCount, result.Message.Thinking);
             }
             catch (Exception ex) when (ex is HttpRequestException or TaskCanceledException && !cancellationToken.IsCancellationRequested)
             {