Allow duplicate refable node names across packages

[MichelleArk]

resolves: #7446
resolves: #1269

Description

• removes DuplicateResourceNameError call in manifest parsing
• uses _find_unique_ids_for_package in RefableLookup
• raises AmbiguousResourceNameRefError in RefableLookup.get_unique_id if multiple unique_ids found
• plumbs caller node (source_node) through RefableLookup for node-aware CompilationError message

Checklist

• I have read the contributing guide and understand what's expected of me
• I have signed the CLA
• I have run this code in development and it appears to resolve the stated issue
• This PR includes tests, or tests are not required/relevant for this PR
• I have opened an issue to add/update docs, or docs changes are not required/relevant for this PR
• I have run changie new to create a changelog entry

Compilation Error in model model_downstream (models/model_downstream.sql)
  dbt found multiple potential nodes when referencing "model" - ['model.project_b.model', 'model.project_a.model'].
  To fix this, specify which package to use as the first argument to 'ref' (one of: ['project_b', 'project_a']).

[github-actions]

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[gshank]

Looks good! It's actually surprising that it didn't take more than this.

[jtcohen6]

nice!! took it for a spin, & it spins

shall we queue up #1269 to close? :)

[jtcohen6]

Ah, something that's still not working: attaching yaml properties to the correct node in the case of duplicates. (This was also the blocker to merging #3053 a few years ago.)

# packages.yml
packages:
  - local: package_a
  - local: package_b

-- package_a/models/my_model.sql
select 1 as id

# package_a/models/schema.yml
models:
  - name: my_model
    description: My cool model

-- package_b/models/my_model.sql
{{ config(alias="something_else") }}
select 1 as id

-- models/another_model.sql
select * from {{ ref('package_a', 'my_model') }}

$ dbt run
06:40:32  Running with dbt=1.6.0-a1
...
Compilation Error
  When referencing 'my_model', dbt found nodes in multiple packages: 'model.package_b.my_model', 'model.package_a.my_model'
  To fix this, use two-argument 'ref', with the package name first: 'package_b' or 'package_a'

Goal: It should be possible to define yaml properties for a model within the same package as that model.

(In the future, we could look to support "overrides" of the package resource from the root project, similar to how we do with sources. That's definitely out of scope for now.)

[MichelleArk]

@jtcohen6 - Pushed up a fix for defining yaml properties on a model within the same package as that model.