IBKR connector: non-string parameters (int/number/bool) serialized as strings, fail JSON schema validation

### What happened?

Any IBKR connector tool that takes a non-string parameter (integer, number, or boolean) fails JSON schema validation before the request reaches IBKR's API. Tools with only string or no parameters (get_account_positions, get_account_summary, get_account_balances, search_contracts) work correctly.

### What did you expect to happen?

Integer, number, and boolean parameters should be passed through in their declared types and validate successfully against the tool's JSON schema, allowing the request to reach the IBKR API normally.

### Steps to reproduce

Connect the Interactive Brokers (IBKR) connector on claude.ai (Android app)
Call get_price_snapshot with an integer contract_id (e.g. 265598)
Observe validation error: "string found, integer expected"
Same result calling get_price_history (contract_id + outside_rth) and create_order_instruction (contract_id, quantity, limit_price)

### Area

MCP Connector (adding/managing servers)

### MCP Server (if applicable)

Interactive Brokers (IBKR)

### Error messages or logs

```shell
Tool (get_price_snapshot) input validation failed: JSON schema validation errors: [/contract_id: string found, integer expected]
Tool (get_price_history) input validation failed: JSON schema validation errors: [/contract_id: string found, integer expected, /outside_rth: string found, boolean expected]
Tool (create_order_instruction) input validation failed: JSON schema validation errors: [/contract_id: string found, integer expected, /quantity: string found, number expected, /limit_price: string found, number expected]
```

### Additional context

Environment: claude.ai mobile app, Android, first-party IBKR connector.
Ruled out session/token issue: reproduced identically after (1) revoking third-party access in IBKR Client Portal (Settings → Third Party Consents → Revoke Access), (2) disconnecting the connector in Claude's app settings, (3) fully reconnecting via fresh OAuth.
Impact: blocks all price/history lookups and order-instruction creation for this connector.