Fix/sqlcatalog iceberg type filter

[avison9]

Rationale for this change

SqlCatalog's iceberg_tables table can be shared with iceberg-java/iceberg-rust clients, which
store both tables and views there using an iceberg_type column (TABLE/VIEW), filtering every
lookup with WHERE (iceberg_type = 'TABLE' OR iceberg_type IS NULL) (see
JdbcUtil.java#L168).
PyIceberg had neither the column nor the filter, so a view row written by another implementation
would be silently treated as a table by load_table, drop_table, rename_table, and commit_table.

Before:

catalog.drop_table(("ns", "sales_summary"))  # 'sales_summary' is actually a VIEW row
# No error — the view's row is silently deleted.

After:

catalog.drop_table(("ns", "sales_summary"))
# raises NoSuchTableError: Table does not exist: ns.sales_summary

This PR builds on #3263 (cherry-picked here, unmerged, authored by @rchowell), which adds the
iceberg_type column, an opt-in idempotent v0→v1 migration, and filters list_tables. On top of
that, it extracts a small _iceberg_type_filter() helper (as suggested in #3337) and applies it to
load_table, drop_table, and rename_table. commit_table needed no direct change since it
already delegates its existence check to load_table.

Note on scope: a prior attempt at #3337 (#3525) tried to add the column and the filtering in one
PR, but was closed after review feedback preferred keeping #3263's column/migration approach
separate from the filtering logic. This PR keeps that separation by adopting #3263's commits as-is
and adding only the filtering on top.

Are these changes tested?

Yes, i added test_load_table_ignores_view_rows, test_drop_table_ignores_view_rows, and
test_rename_table_ignores_view_rows in tests/catalog/test_sql.py, each inserting a raw VIEW
row and confirming the affected operation now raises NoSuchTableError instead of touching it.
Verified all three fail without the fix. Full suite: 3796 passed, 0 failed.

Are there any user-facing changes?

Yes! SqlCatalog.load_table, drop_table, and rename_table now correctly ignore VIEW rows
written by other Iceberg implementations sharing the same catalog table, instead of silently
reading, deleting, or renaming them. New optional schema_version catalog property (from #3263)
controls opt-in migration of existing v0 catalogs. Please apply the changelog label.