[core] Fix copyWithLatestSchema option precedence

[thswlsqls]

Purpose

fix #4957

• copyWithLatestSchema() now lets the latest committed schema options override stale options from the current table copy, so altered option values survive a refresh.
• Removes the obsolete TODO that described the previous broken precedence.

Tests

• Added AppendOnlySimpleTableTest#testCopyWithLatestSchemaPicksUpAlteredOptionValues: alter snapshot.num-retained.max to 10, then assert copyWithLatestSchema() reflects it.
• Failed before the fix with expected: 10 but was: 100; passes after.
• mvn -pl paimon-core -am clean install ran the normal checks (checkstyle/spotless/rat); only PostgresqlCatalogTest was skipped for local Docker absence.