[AINode] Refactor table forecast function

[CRZbulabula]

To prepare for supporting multi/co-variable models in AINode, we refactor the table forecast function in this PR, main ideas and updates include:

1. When invoking table value forecast function, all specified input columns should be delivered to AINode as the model's input channels.
2. When invoking table value forecast function, the users are suggested to specify the PREDICATED_COLUMNS. In this way, the IoTDB can realize the count and data types of the forecast result.

[Copilot]

Pull Request Overview

This pull request refactors the ForecastTableFunction to separate input column types from predicted column types, addressing the distinction between columns used as inputs for model forecasting and columns that are predicted as outputs.

• Split the single types field into inputColumnTypes and predicatedColumnTypes for clearer separation of concerns
• Fixed logic to properly track which columns are inputs to the model versus which columns will have predicted outputs
• Updated serialization/deserialization to handle both type lists separately

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
TableFunctionTest.java	Updated test assertions to include the new inputColumnTypes parameter in ForecastTableFunctionHandle construction
UDTFForecast.java	Removed Chinese comments and simplified code formatting
ForecastTableFunction.java	Core refactoring to split types into inputColumnTypes and predicatedColumnTypes, updated serialization/deserialization, and refined column tracking logic
.gitignore	Removed /iotdb/__init__.py from ignore list

---

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[Copilot]

Variable 'Type type' is never read.

Suggested change

	for (Type type : functionHandle.inputColumnTypes) {
	// AINode currently only accept double input
	inputTsDataTypeList.add(TSDataType.DOUBLE);
	}
	this.inputTsBlockBuilder = new TsBlockBuilder(inputTsDataTypeList);
	this.inputColumnAppenderList = new ArrayList<>(functionHandle.inputColumnTypes.size());
	for (Type type : functionHandle.inputColumnTypes) {
	for (int i = 0; i < functionHandle.inputColumnTypes.size(); i++) {
	// AINode currently only accept double input
	inputTsDataTypeList.add(TSDataType.DOUBLE);
	}
	this.inputTsBlockBuilder = new TsBlockBuilder(inputTsDataTypeList);
	this.inputColumnAppenderList = new ArrayList<>(functionHandle.inputColumnTypes.size());
	for (int i = 0; i < functionHandle.inputColumnTypes.size(); i++) {

[Copilot]

Variable 'Type type' is never read.

Suggested change

	for (Type type : functionHandle.inputColumnTypes) {
	for (int i = 0; i < functionHandle.inputColumnTypes.size(); i++) {

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

❌ Patch coverage is 28.57143% with 30 lines in your changes missing coverage. Please review.
✅ Project coverage is 38.72%. Comparing base (685141a) to head (13b90b1).
⚠️ Report is 4 commits behind head on master.

Files with missing lines	Patch %	Lines
...relational/function/tvf/ForecastTableFunction.java	30.00%	28 Missing ⚠️
...he/iotdb/db/queryengine/plan/udf/UDTFForecast.java	0.00%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #16686      +/-   ##
============================================
- Coverage     38.72%   38.72%   -0.01%     
  Complexity      207      207              
============================================
  Files          4986     4986              
  Lines        330362   330376      +14     
  Branches      42000    42007       +7     
============================================
- Hits         127938   127935       -3     
- Misses       202424   202441      +17     

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[RkGrit]

LGTM!
But why not also support multi/co-variable models for the tree value forecast function?