v0.11.0 — Tool surface consolidation (13 → 9)

Breaking

• Tool surface consolidated from 13 to 9 tools: Five tools dropped and two merged into one. The full contract is already injected into the system prompt by ClaudePromptRenderer, so the dropped tools were redundant from an analytics-agent perspective.
• list_schemas removed: The allowed-schemas set is implicit in the allowed-tables list that the prompt renderer already injects.
• list_tables removed: The prompt renderer already injects the full allowed-tables list. Per-table column details remain available via describe_table.
• get_contract_info removed: Contract name, allowed tables, rules, and limits are all in the prompt. The one dynamic field the tool exposed — remaining session budget — is now embedded in every run_query response under session.remaining.
• validate_query + query_cost_estimate merged into inspect_query: Both tools wrapped the same underlying Validator.validate() call (which internally runs Layer 1 + EXPLAIN). The merge removes a "which tool do I call?" decision. Response is structured JSON with valid, violations, warnings, log_messages, schema_valid, explain_errors, pending_result_checks, and — when an adapter is configured — estimated_cost_usd and estimated_rows.

Changed

• run_query response: Success responses now include a session.remaining block mirroring ContractSession.remaining() (elapsed seconds, retries remaining, token budget remaining, cost remaining). Blocked responses append a one-line Remaining: {...} suffix with the same data.
• ValidationResult dataclass: Gains three additive fields — estimated_rows: int | None, schema_valid: bool = True, and explain_errors: list[str] = []. Populated in Validator.validate() when an ExplainAdapter is configured. Defaults are safe for existing callers.

Migration

• Replace validate_query(sql) calls with inspect_query(sql). The response is JSON rather than a status string; parse valid, violations, and warnings. Cost and row estimates live under the same response.
• Replace query_cost_estimate(sql) calls with inspect_query(sql). Cost and row fields are now nested alongside validation fields.
• If an agent previously called get_contract_info, read remaining budget from run_query responses (data["session"]["remaining"]) instead. Static contract metadata is already in the system prompt.
• list_schemas and list_tables have no replacements — the prompt already contains this information.