Remove deprecated code in MiniMax model support

[markpollack]

Deprecated code from the switch to the new tool calling infrastructure from the function calling infrastructure need to happen.

Here is the general idea of what needs to happen.

The current design uses the ToolCallingManager to execute the tools. In terms of expected changes,

1. The ChatOptions would extend from ToolCallingChatOptions instead of FunctionCallingOptions
2. The flag proxyToolCalls is replaced by the internalToolExecutionsEnabled to check if the tool execution is handled by Spring AI (this is set to true by default)
3. All the functionCallback options are replaced by toolCallback and toolNames
4. The ChatModel no longer extends from AbstractToolCallSupport but has the toolCallingManager reference to execute the tools
5. There is ToolExecutionEligibilityPredicate which handles the delegation to verify the enabling of tool execution.

Please take a look at this PR which originally introduced the toolcalling manager support to the models: 52198ed#diff-e5cb77ca54425cc7c57b08f1d70da4118eaf2c0377d381b1d184ace96d6f6e89

[ilayaperumalg]

This is completed via 49e1dd1