feat(runtime): add planner reflection history with rationale and thinking

- ToolCallDecision captures thinking blocks and pre-tool text output
- AnthropicToolCallingClient supports optional extended thinking (budget_tokens + beta header)
- PlannedStep carries rationale and thinking from each LLM decision
- WorldEvent replaces scene_summary with rationale/thinking/page fields (backward-compatible)
- AI planner system prompt instructs reflection before each tool call
- _history_summary() emits compact {page, rationale, action, success} dicts
- Cloud DB migration 0011 adds nullable rationale/thinking columns to planner_decision_log
- OpenAI client extracts reasoning_content into thinking field

runtime/planner.py

@@ -19,6 +19,12 @@ class PlannedStep:
     # The actual prompt sent to the LLM for this step (AI planners only).
     # ``None`` for non-LLM planners; TaskRunner falls back to the task goal.
     prompt: str | None = None
+    # Pre-tool text block emitted by the model before the tool call.
+    # None when the model omits a text block or for non-LLM planners.
+    rationale: str | None = None
+    # Extended thinking / reasoning content from the model.
+    # None when not enabled or not present.
+    thinking: str | None = None
 
 
 class Planner: