[fix](nereids) Fix table name case-sensitivity issue when binding columns for external tables

[CalvinKirs]

…

Proposed changes

Fix the issue where column binding fails for external tables (Hive, Iceberg, etc.) when users reference table names with original case in SQL.
Problem
When querying external Hive tables, the following SQL fails: SELECT * FROM TPCH50.DIM_LINEITEM_CORE_OD001_V1
WHERE DIM_LINEITEM_CORE_OD001_V1.dt = '20260108' LIMIT 10; -- Error: Unknown column 'dt' in 'DIM_LINEITEM_CORE_OD001_V1' in FILTER clause But using an alias works:
SELECT * FROM TPCH50.DIM_LINEITEM_CORE_OD001_V1 AS DIM_LINEITEM_CORE_OD001_V1 WHERE DIM_LINEITEM_CORE_OD001_V1.dt = '20260108' LIMIT 10; -- Success
Root Cause

1. Hive Metastore stores table names in lowercase (e.g., dim_lineitem_core_od001_v1)
2. The slot qualifier uses table.getName() which returns the lowercase HMS table name
3. Users reference the table with original case in SQL (e.g., DIM_LINEITEM_CORE_OD001_V1.dt)
4. ExpressionAnalyzer.sameTableName() performs case-sensitive comparison when lower_case_table_names != 1, causing binding to fail Solution
   Change sameTableName() to always use case-insensitive comparison for table names. This is consistent with:

• Catalog name comparison (already case-insensitive at line 1079)
• Database name comparison (already case-insensitive at line 1092)

What problem does this PR solve?

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

Release note

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• Behavior changed:

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[Thearas]

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