fix(cli): explicitly close tree-sitter cursors and ast (#8243)

Fix #818

See also:
 smacker/go-tree-sitter#183
 smacker/go-tree-sitter#182

---

### Changes are visible to end-users: yes

- Searched for relevant documentation and updated as needed: yes
- Breaking change (forces users to change their own code or config): no
- Suggested release notes appear below: yes

Ensure `configure` tree-sitter resources are explicitly cleaned up.

### Test plan

- Covered by existing test cases

GitOrigin-RevId: 35c3509f084f0d7c2e01a9d11faa2519462dc46b

Author: jbedard

gazelle/common/treesitter/parser.go

@@ -56,6 +56,10 @@ type AST interface {
 	// TODO: delete
 	QueryStrings(query TreeQuery, returnVar string) []string
 	RootNode() *sitter.Node
+
+	// Release all resources related to this AST.
+	// The AST is most likely no longer usable after this call.
+	Close()
 }
 type treeAst struct {
 	lang       LanguageGrammar
@@ -67,6 +71,12 @@ type treeAst struct {
 
 var _ AST = (*treeAst)(nil)
 
+func (tree *treeAst) Close() {
+	tree.sitterTree.Close()
+	tree.sitterTree = nil
+	tree.sourceCode = nil
+}
+
 func (tree *treeAst) String() string {
 	return fmt.Sprintf("treeAst{\n lang: %q,\n filePath: %q,\n AST:\n  %v\n}", tree.lang, tree.filePath, tree.sitterTree.RootNode().String())
 }

gazelle/common/treesitter/queries.go

@@ -37,6 +37,7 @@ func (tree *treeAst) QueryStrings(query TreeQuery, returnVar string) []string {
 
 	// Execute the query.
 	qc := sitter.NewQueryCursor()
+	defer qc.Close()
 	qc.Exec(sitterQuery.q, rootNode)
 
 	// Collect string from the query results.
@@ -83,6 +84,7 @@ func (tree *treeAst) Query(query TreeQuery) <-chan ASTQueryResult {
 	// Execute the query.
 	go func() {
 		qc := sitter.NewQueryCursor()
+		defer qc.Close()
 		qc.Exec(q.q, rootNode)
 
 		for {
@@ -167,6 +169,7 @@ func (tree *treeAst) QueryErrors() []error {
 
 	// Execute the import query
 	qc := sitter.NewQueryCursor()
+	defer qc.Close()
 	qc.Exec(query.q, node)
 
 	// Collect import statements from the query results

gazelle/js/parser/parser.go

@@ -58,6 +58,7 @@ func ParseSource(filePath string, sourceCode []byte) (ParseResult, []error) {
 	}
 
 	if tree != nil {
+		defer tree.Close()
 		rootNode := tree.RootNode()
 		rootNodeChildCount := int(rootNode.NamedChildCount())
 

gazelle/kotlin/parser/parser.go

@@ -45,6 +45,7 @@ func (p *treeSitterParser) Parse(filePath string, sourceCode []byte) (*ParseResu
 	}
 
 	if tree != nil {
+		defer tree.Close()
 		rootNode := tree.RootNode()
 
 		// Extract imports from the root nodes