[Feature]: SQL code auto-completion support in DataAgent

**Title:** Does DataAgent plan to support SQL code auto-completion?

**Is your feature request related to a problem? Please describe.**

I am evaluating AgentScope-Java DataAgent for data development and data analysis scenarios.

Currently, DataAgent appears to provide SQL-related agent capabilities, such as data source discovery, table/schema description, SQL analysis, SQL preview execution, chart rendering, and report generation. However, I could not find whether it supports or plans to support SQL code auto-completion.

In data development platforms, users often write SQL manually. Without SQL auto-completion, users may need to frequently switch between schema documentation and the SQL editor, which reduces development efficiency and increases the chance of writing incorrect table names, column names, functions, or join conditions.

**Describe the solution you'd like**

I would like to know whether DataAgent has any plan to support SQL code auto-completion, especially editor-level SQL completion features such as:

* table name completion
* column name completion
* database/schema completion
* SQL keyword and function completion
* context-aware completion based on the current SQL cursor position
* join condition suggestions based on table metadata
* optional LLM-assisted SQL completion or correction

Ideally, this could work with common frontend SQL editors such as Monaco Editor or CodeMirror, while the backend provides metadata and completion suggestions through AgentScope-Java tools, MCP tools, or DataAgent-specific services.

**Describe alternatives you've considered**

One alternative is to implement SQL auto-completion outside DataAgent as a separate service, for example:

* frontend editor completion using Monaco Editor or CodeMirror
* backend metadata APIs for databases, tables, and columns
* SQL parser-based context analysis
* MCP tools such as `list_data_sources`, `describe_table`, `complete_sql`, `validate_sql`, and `run_sql_preview`
* optional LLM-based SQL generation or correction

However, if DataAgent already has a planned direction for SQL code auto-completion, it would be better to align with the official design instead of building a separate implementation.

**Additional context**

My use case is an internal data development platform. We are considering AgentScope-Java / Harness / Builder / DataAgent for enterprise data assistant scenarios, including SQL assistance, metadata lookup, report generation, and workflow guidance.

I would like to confirm:

1. Does DataAgent currently support SQL code auto-completion?
2. If not, is SQL code auto-completion on the roadmap?
3. If this feature is not planned, what would be the recommended extension point in AgentScope-Java to implement it?