fix: fix DuckDB LOAD syntax support

Related to #882

---

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crates/lib-dialects/src/duckdb.rs

@@ -12,13 +12,15 @@ use sqruff_lib_core::parser::parsers::StringParser;
 use sqruff_lib_core::parser::segments::meta::MetaSegment;
 use sqruff_lib_core::vec_of_erased;
 
+use crate::{ansi, postgres};
+
 pub fn dialect() -> Dialect {
     raw_dialect().config(|dialect| dialect.expand())
 }
 
 pub fn raw_dialect() -> Dialect {
-    let ansi_dialect = super::ansi::raw_dialect();
-    let postgres_dialect = super::postgres::dialect();
+    let ansi_dialect = ansi::raw_dialect();
+    let postgres_dialect = postgres::dialect();
     let mut duckdb_dialect = postgres_dialect;
     duckdb_dialect.name = DialectKind::Duckdb;
 
@@ -60,6 +62,15 @@ pub fn raw_dialect() -> Dialect {
                 )
                 .into(),
         ),
+        (
+            "LoadStatementSegment".into(),
+            Sequence::new(vec_of_erased![
+                Ref::keyword("LOAD"),
+                Ref::new("SingleIdentifierGrammar"),
+            ])
+            .to_matchable()
+            .into(),
+        ),
     ]);
 
     duckdb_dialect.insert_lexer_matchers(
@@ -177,5 +188,17 @@ pub fn raw_dialect() -> Dialect {
         .to_matchable(),
     );
 
+    duckdb_dialect.replace_grammar(
+        "StatementSegment",
+        postgres::statement_segment().copy(
+            Some(vec_of_erased![Ref::new("LoadStatementSegment")]),
+            None,
+            None,
+            None,
+            vec![],
+            false,
+        ),
+    );
+
     duckdb_dialect
 }

crates/lib-dialects/test/fixtures/dialects/duckdb/load_statement.sql

@@ -0,0 +1 @@
+LOAD spatial;

crates/lib-dialects/test/fixtures/dialects/duckdb/load_statement.yml

@@ -0,0 +1,5 @@
+file:
+- statement:
+  - keyword: LOAD
+  - naked_identifier: spatial
+- statement_terminator: ;