Add graph database and temporal table parsing support

- Add MATCH predicate support in WHERE clauses
- Support chained graph patterns (A-(B)->C-(D)->E)
- Add NOT MATCH support for negated graph patterns
- Add GENERATED ALWAYS AS ROW START/END for temporal columns
- Add PERIOD FOR SYSTEM_TIME parsing in CREATE TABLE
- Add SYSTEM_VERSIONING = ON/OFF table option
- Add SystemTimePeriodDefinition AST type
- Support graph pseudo-columns ($node_id, $edge_id, $from_id, $to_id)
- Make BooleanBinaryExpression implement graphMatchExpression for chained patterns
- Make GraphMatchCompositeExpression implement booleanExpression

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: kyleconroy

ast/boolean_binary_expression.go

@@ -7,5 +7,6 @@ type BooleanBinaryExpression struct {
 	SecondExpression     BooleanExpression `json:"SecondExpression,omitempty"`
 }
 
-func (*BooleanBinaryExpression) node()              {}
-func (*BooleanBinaryExpression) booleanExpression() {}
+func (*BooleanBinaryExpression) node()                 {}
+func (*BooleanBinaryExpression) booleanExpression()    {}
+func (*BooleanBinaryExpression) graphMatchExpression() {}

ast/create_table_statement.go

@@ -41,10 +41,19 @@ type TableDefinition struct {
 	ColumnDefinitions []*ColumnDefinition
 	TableConstraints  []TableConstraint
 	Indexes           []*IndexDefinition
+	SystemTimePeriod  *SystemTimePeriodDefinition
 }
 
 func (t *TableDefinition) node() {}
 
+// SystemTimePeriodDefinition represents PERIOD FOR SYSTEM_TIME clause
+type SystemTimePeriodDefinition struct {
+	StartTimeColumn *Identifier
+	EndTimeColumn   *Identifier
+}
+
+func (s *SystemTimePeriodDefinition) node() {}
+
 // ColumnDefinition represents a column definition in CREATE TABLE
 type ColumnDefinition struct {
 	ColumnIdentifier         *Identifier
@@ -55,6 +64,7 @@ type ColumnDefinition struct {
 	IdentityOptions          *IdentityOptions
 	Constraints              []ConstraintDefinition
 	Index                    *IndexDefinition
+	GeneratedAlways          string // RowStart, RowEnd, etc.
 	IsPersisted              bool
 	IsRowGuidCol             bool
 	IsHidden                 bool

ast/merge_statement.go

@@ -95,6 +95,7 @@ type GraphMatchCompositeExpression struct {
 
 func (g *GraphMatchCompositeExpression) node()                 {}
 func (g *GraphMatchCompositeExpression) graphMatchExpression() {}
+func (g *GraphMatchCompositeExpression) booleanExpression()    {}
 
 // GraphMatchNodeExpression represents a node in a graph match pattern
 type GraphMatchNodeExpression struct {