Add support for Stored Procedures in JDBC driver (Phase 1) (#1051)

## Description
<!-- Provide a brief summary of the changes made and the issue they aim
to address.-->
This PR introduces phase 1 of stored procedure support in the Databricks
JDBC driver.
The driver now supports executing CALL statements that invoke stored
procedures on the server.

Key Capabilities
- ✅ Supports CALL syntax for stored procedure execution (e.g., CALL
my_proc(?, ?)).
- ✅ Supports input parameters, which can be set using standard JDBC APIs
(setInt, setString, etc.).
- ⚙️ Output parameters are currently supported only via SQL scripting
(e.g., procedures returning results via SELECT statements or variables
assigned inside scripts).
- 🚧 This is phase 1 — additional support for true OUT/INOUT parameters
will be introduced in a future phase (full fledged support using
CallableStatement.)

## Testing
<!-- Describe how the changes have been tested-->
Tested using unit tests, will also test manually.

## Additional Notes to the Reviewer
<!-- Share any additional context or insights that may help the reviewer
understand the changes better. This could include challenges faced,
limitations, or compromises made during the development process.
Also, mention any areas of the code that you would like the reviewer to
focus on specifically. -->

Author: gopalldb

NEXT_CHANGELOG.md

@@ -13,6 +13,7 @@
   - Note: Large batches are chunked for execution. If a chunk fails, previous chunks remain committed (no transaction rollback). Consider using staging tables for critical workflows.
 - Added a new config attribute `DisableOauthRefreshToken` to control whether refresh tokens are requested in OAuth exchanges. By default, the driver does not include the `offline_access` scope. If `offline_access` is explicitly provided by the user, it is preserved and not removed.
 - Added Feature-flag integration for SQL Exec API rollout
+- Call statements will return result sets in response
 
 ### Updated
 - Minimized OAuth requests by reducing calls in feature flags and telemetry.

src/main/java/com/databricks/jdbc/api/impl/DatabricksStatement.java

@@ -695,7 +695,8 @@ static boolean shouldReturnResultSet(String query) {
         || GET_PATTERN.matcher(trimmedQuery).find()
         || REMOVE_PATTERN.matcher(trimmedQuery).find()
         || LIST_PATTERN.matcher(trimmedQuery).find()
-        || BEGIN_PATTERN_FOR_SQL_SCRIPT.matcher(trimmedQuery).find();
+        || BEGIN_PATTERN_FOR_SQL_SCRIPT.matcher(trimmedQuery).find()
+        || CALL_PATTERN.matcher(trimmedQuery).find();
 
     // Otherwise, it should not return a ResultSet
   }

src/main/java/com/databricks/jdbc/common/DatabricksJdbcConstants.java

@@ -159,15 +159,17 @@ public enum FakeServiceType {
   public static final Pattern DECLARE_PATTERN =
       Pattern.compile("^(\\s*\\()*\\s*DECLARE", Pattern.CASE_INSENSITIVE);
   public static final Pattern PUT_PATTERN =
-      Pattern.compile("^(\\s*\\()*\\s*GET", Pattern.CASE_INSENSITIVE);
-  public static final Pattern GET_PATTERN =
       Pattern.compile("^(\\s*\\()*\\s*PUT", Pattern.CASE_INSENSITIVE);
+  public static final Pattern GET_PATTERN =
+      Pattern.compile("^(\\s*\\()*\\s*GET", Pattern.CASE_INSENSITIVE);
   public static final Pattern REMOVE_PATTERN =
       Pattern.compile("^(\\s*\\()*\\s*REMOVE", Pattern.CASE_INSENSITIVE);
   public static final Pattern LIST_PATTERN =
       Pattern.compile("^(\\s*\\()*\\s*LIST", Pattern.CASE_INSENSITIVE);
   public static final Pattern INSERT_PATTERN =
       Pattern.compile("^(\\s*\\()*\\s*INSERT\\s+INTO", Pattern.CASE_INSENSITIVE);
+  public static final Pattern CALL_PATTERN =
+      Pattern.compile("^(\\s*\\()*\\s*CALL", Pattern.CASE_INSENSITIVE);
 
   /** Maximum number of parameters allowed in a single Databricks query */
   public static final int MAX_QUERY_PARAMETERS = 256;

src/test/java/com/databricks/jdbc/api/impl/DatabricksStatementTest.java

@@ -675,6 +675,14 @@ public void testShouldReturnResultSet_CommentSurroundingQuery() {
     assertTrue(DatabricksStatement.shouldReturnResultSet(query));
   }
 
+  @Test
+  public void testShouldReturnResultSet_CallStatement() {
+    String query =
+        "-- Single-line comment\n/* Multi-line comment */ CALL send_notifications(12); /* Another comment */ -- End comment";
+    assertTrue(DatabricksStatement.shouldReturnResultSet(query));
+    assertTrue(DatabricksStatement.shouldReturnResultSet("CALL send_notifications(12);"));
+  }
+
   @Test
   public void testShouldReturnResultSet_StartWithBegin() {
     assertTrue(DatabricksStatement.shouldReturnResultSet("BEGIN"));