Add Python support to default-python template (#3785)

## Changes
Add Python support to `default-python` template. 

The option to enable PyDABs is hidden and only available through
input.json. Enabling will be done together with marking "python" configs
as non-experimental by adding a new template based on the
`default-python` template.

See non-generated code in c1159c7

## Why
This makes the PyDABs template similar to the existing `default-python`.
Previously, it wasn't possible because `default-python` Python didn't
use UV.

## Tests
Acceptance tests for:
- consistency between resources declared in YAML vs Python
- formatting and snapshots for generated Python files in `resources`
directory
- output of "classic" configuration as end-to-end example

Author: kanterov

.codegen.json

@@ -8,6 +8,7 @@
         "experimental/python/pyproject.toml": "version = \"$VERSION\"",
         "experimental/python/uv.lock": "name = \"databricks-bundles\"\nversion = \"$VERSION\"",
         "libs/template/templates/experimental-jobs-as-code/library/versions.tmpl": "{{define \"latest_databricks_bundles_version\" -}}$VERSION{{- end}}"
+        "libs/template/templates/default-python/library/versions.tmpl": "{{define \"latest_databricks_bundles_version\" -}}$VERSION{{- end}}"
     },
     "toolchain": {
         "required": [

acceptance/bundle/templates/pydabs/check-consistency/input.json.tmpl

@@ -0,0 +1,8 @@
+{
+  "project_name": "my_pydabs",
+  "include_notebook": "$INCLUDE_NOTEBOOK",
+  "include_dlt": "$INCLUDE_DLT",
+  "include_python": "$INCLUDE_PYTHON",
+  "enable_pydabs": "$enable_pydabs",
+  "serverless": "$SERVERLESS"
+}

acceptance/bundle/templates/pydabs/check-consistency/out.test.toml

@@ -0,0 +1,36 @@
+== Collecting resources into ./enable_pydabs=yes
+
+>>> [CLI] bundle init default-python --config-file ./input.json
+
+Welcome to the default Python template for Databricks Asset Bundles!
+Workspace to use (auto-detected, edit in 'my_pydabs/databricks.yml'): [DATABRICKS_URL]
+
+✨ Your new project has been created in the 'my_pydabs' 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.
+
+>>> uv venv --quiet
+
+>>> uv pip install --quiet [DATABRICKS_BUNDLES_WHEEL]
+
+>>> [CLI] bundle validate --output json
+== Collecting resources into ./enable_pydabs=no
+
+>>> [CLI] bundle init default-python --config-file ./input.json
+
+Welcome to the default Python template for Databricks Asset Bundles!
+Workspace to use (auto-detected, edit in 'my_pydabs/databricks.yml'): [DATABRICKS_URL]
+
+✨ Your new project has been created in the 'my_pydabs' 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.
+
+>>> uv venv --quiet
+
+>>> uv pip install --quiet [DATABRICKS_BUNDLES_WHEEL]
+
+>>> [CLI] bundle validate --output json
+
+>>> diff -Naur enable_pydabs=yes enable_pydabs=no

acceptance/bundle/templates/pydabs/check-consistency/output.txt

@@ -0,0 +1,21 @@
+for enable_pydabs in yes no; do
+    echo "== Collecting resources into ./enable_pydabs=$enable_pydabs"
+
+    enable_pydabs=$enable_pydabs envsubst < input.json.tmpl > input.json
+
+    trace $CLI bundle init default-python --config-file ./input.json
+
+    (
+        cd my_pydabs
+
+        trace uv venv --quiet
+        trace uv pip install --quiet $DATABRICKS_BUNDLES_WHEEL
+
+        trace $CLI bundle validate --output json | jq "pick(.resources)" > ../enable_pydabs=$enable_pydabs
+    )
+
+    rm -rf my_pydabs input.json
+done
+
+trace diff -Naur enable_pydabs=yes enable_pydabs=no
+rm enable_pydabs=yes enable_pydabs=no

acceptance/bundle/templates/pydabs/check-consistency/script

@@ -0,0 +1,5 @@
+[EnvMatrix]
+INCLUDE_NOTEBOOK = ["yes", "no"]
+INCLUDE_DLT = ["yes", "no"]
+INCLUDE_PYTHON = ["yes", "no"]
+SERVERLESS = ["yes", "no"]

acceptance/bundle/templates/pydabs/check-consistency/test.toml

@@ -0,0 +1,8 @@
+{
+  "project_name": "my_pydabs",
+  "include_notebook": "$INCLUDE_NOTEBOOK",
+  "include_dlt": "$INCLUDE_DLT",
+  "include_python": "$INCLUDE_PYTHON",
+  "enable_pydabs": "yes",
+  "serverless": "$SERVERLESS"
+}

acceptance/bundle/templates/pydabs/check-formatting/input.json.tmpl

@@ -0,0 +1,16 @@
+
+>>> [CLI] bundle init default-python --config-file ./input.json
+
+Welcome to the default Python template for Databricks Asset Bundles!
+Workspace to use (auto-detected, edit in 'my_pydabs/databricks.yml'): [DATABRICKS_URL]
+
+✨ Your new project has been created in the 'my_pydabs' 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.
+
+>>> find my_pydabs -mindepth 1 ! -name pyproject.toml ! -regex .*/resources.* -delete
+
+>>> ruff format --quiet --diff --check my_pydabs
+
+>>> yamlcheck.py

acceptance/bundle/templates/pydabs/check-formatting/out.test.toml

@@ -0,0 +1,11 @@
+envsubst < input.json.tmpl > input.json
+
+trace $CLI bundle init default-python --config-file ./input.json
+
+# only keep relevant files for snapshots
+trace find my_pydabs -mindepth 1 ! -name 'pyproject.toml' ! -regex '.*/resources.*' -delete
+
+trace ruff format --quiet --diff --check my_pydabs
+trace yamlcheck.py
+
+rm -rf my_pydabs input.json