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_config.py

@@ -15,6 +15,7 @@ ENABLED_ENV = "AI_PLANNER_ENABLED"
 PROVIDER_ENV = "AI_PLANNER_PROVIDER"
 MODEL_ENV = "AI_PLANNER_MODEL"
 TIMEOUT_ENV = "AI_PLANNER_TIMEOUT_SECONDS"
+THINKING_BUDGET_ENV = "AI_PLANNER_THINKING_BUDGET_TOKENS"
 
 SUPPORTED_PROVIDERS = frozenset(DEFAULT_MODEL_BY_PROVIDER)
 
@@ -25,6 +26,7 @@ class PlannerConfig:
     provider: str = DEFAULT_PROVIDER
     model: str = ""
     timeout: float = DEFAULT_TIMEOUT_SECONDS
+    thinking_budget_tokens: int | None = None
 
     def resolved_model(self) -> str:
         return self.model or DEFAULT_MODEL_BY_PROVIDER[self.provider]
@@ -37,6 +39,7 @@ def load_config(env: Mapping[str, str] | None = None) -> PlannerConfig:
         provider=_parse_provider(values.get(PROVIDER_ENV)),
         model=values.get(MODEL_ENV) or "",
         timeout=_parse_timeout(values.get(TIMEOUT_ENV)),
+        thinking_budget_tokens=_parse_thinking_budget(values.get(THINKING_BUDGET_ENV)),
     )
 
 
@@ -61,3 +64,13 @@ def _parse_timeout(value: str | None) -> float:
     except ValueError:
         return DEFAULT_TIMEOUT_SECONDS
     return timeout if timeout > 0 else DEFAULT_TIMEOUT_SECONDS
+
+
+def _parse_thinking_budget(value: str | None) -> int | None:
+    if value is None:
+        return None
+    try:
+        budget = int(value)
+    except ValueError:
+        return None
+    return budget if budget > 0 else None