Add default project name and success message to default-scala template (#4661)

## Changes

This adds makes the `project_name` and a `success_message` fields
consistent with other templates.

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: lennartkats-db

NEXT_CHANGELOG.md

@@ -11,6 +11,7 @@
 ### Bundles
 * engine/direct: Fix permanent drift on experiment name field ([#4627](https://github.com/databricks/cli/pull/4627))
 * engine/direct: Fix permissions state path to match input config schema ([#4703](https://github.com/databricks/cli/pull/4703))
+* Add default project name and success message to default-scala template ([#4661](https://github.com/databricks/cli/pull/4661))
 
 ### Dependency updates
 

acceptance/bundle/templates/default-scala/output.txt

@@ -5,4 +5,8 @@ Welcome to the default-scala template for Databricks Asset Bundles!
 
 A workspace was selected based on your current profile. For information about how to change this, see https://docs.databricks.com/dev-tools/cli/profiles.html.
 workspace_host: [DATABRICKS_URL]
-✨ Successfully initialized template
+
+✨ Your new project has been created in the 'my_default_scala' directory!
+
+Please refer to the README.md file for "getting started" instructions.
+See also the documentation at https://docs.databricks.com/dev-tools/bundles/index.html.

libs/template/templates/default-scala/databricks_template_schema.json

@@ -3,6 +3,7 @@
   "properties": {
     "project_name": {
       "type": "string",
+      "default": "my_scala_project",
       "description": "\nPlease provide a unique name for this project.\nproject_name",
       "order": 1,
       "pattern": "^[A-Za-z_][A-Za-z0-9-_]+$",
@@ -54,5 +55,6 @@
       "description": "\nPlease provide an initial schema during development.\ndefault_schema",
       "order": 6
     }
-  }
+  },
+  "success_message": "\n✨ Your new project has been created in the '{{.project_name}}' directory!\n\nPlease refer to the README.md file for \"getting started\" instructions.\nSee also the documentation at https://docs.databricks.com/dev-tools/bundles/index.html."
 }