Fix ref macro override to support package args and version keyword

[haritamar]

Summary

Fix the ref macro override in builtins.sql to correctly support all dbt ref() calling conventions.

Description

The current override has the signature ref(model_name, v=None), which breaks two valid dbt calling conventions:

1. Two-positional-arg form — ref('package', 'model') for cross-package/project refs: the second positional arg was incorrectly interpreted as a version number instead of a model name.
2. version keyword argument — ref('model', version=1) was not accepted at all (only v= was supported).

The fix adopts the correct interface per the dbt docs on builtins overrides:

-{%- macro ref(model_name, v=None) -%}
-  {%- set relation = builtins.ref(model_name, v=v) -%}
-  {%- if execute and graph -%}
-    {%- set model = graph.nodes.values() | selectattr("name", "equalto", model_name) | list | first -%}
+{%- macro ref(model_name_or_package, model_name=none, v=none, version=none) -%}
+  {%- set effective_version = v if v is not none else version -%}
+  {%- if model_name is not none -%}
+    {%- set relation = builtins.ref(model_name_or_package, model_name, v=effective_version) -%}
+    {%- set _model_name = model_name -%}
+  {%- else -%}
+    {%- set relation = builtins.ref(model_name_or_package, v=effective_version) -%}
+    {%- set _model_name = model_name_or_package -%}
+  {%- endif -%}
+  {%- if execute and graph -%}
+    {%- set model = graph.nodes.values() | selectattr("name", "equalto", _model_name) | list | first -%}

Note: the same bug was independently identified and worked around in elementary-data/elementary, which added a local ref override specifically to compensate for this dbt-dremio issue.

Test Results

Manually verified the macro logic against all calling forms:

• ref('model') — unchanged behaviour
• ref('package', 'model') — now works correctly
• ref('model', v=1) — unchanged behaviour
• ref('model', version=1) — now works correctly

Changelog

• Added a summary of what this PR accomplishes to CHANGELOG.md

Contributor License Agreement

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Related Issue

Fixes #232

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