Support Dynamic References in Dataset Upload Block registration_tags input

[Grantimus9]

So far, this PR implements the following tests to support each given requirement to enable registration_tags to accept both strings and references to other strings and references to other arrays, which will be flattened appropriately.

Requirement 1: Should Resolve Referenced Strings

Pattern: ["literal1", "$inputs.string_tag"] where string_tag = "some_string_value" → ["literal1", "some_string_value"]

Schema Parsing Tests (test_schema_parser.py)

• test_parse_block_manifest_when_manifest_defines_list_of_strings_and_string_selectors (line 536)
  • Verifies manifest parsing creates both primitive and selector definitions for mixed arrays with List[Union[WorkflowParameterSelector(STRING_KIND), str]]
• test_parse_block_manifest_when_manifest_defines_union_of_string_and_string_selector (line 591)
  • Tests non-array union of string or selector: Union[str, WorkflowParameterSelector]
• test_parse_block_manifest_when_manifest_defines_mixed_selectors_and_step_output_selectors (line 795)
  • Verifies mixed arrays with multiple selector types (WorkflowParameter and StepOutput)

Parameter Resolution Tests (test_step_input_assembler.py)

• test_unfold_parameters_when_array_contains_mixed_literal_strings_and_dynamic_selectors (line 346)
  • Tests runtime resolution of mixed array with one dynamic selector: ["static-tag-1", "dynamic-tag-value", "static-tag-2"]
• test_unfold_parameters_when_array_contains_mixed_literals_and_multiple_dynamic_selectors (line 380)
  • Tests multiple dynamic selectors in one array are all resolved in their correct positions
• test_unfold_parameters_when_array_selector_resolves_to_batch (line 450)
  • Tests batched selector where each batch element gets different resolved values
• test_unfold_parameters_when_array_has_mixed_literals_and_batch_selectors (line 492)
  • Tests mixed literals with both batch and non-batch selectors (non-batch broadcasts, batch unfolds)

Block-Level Tests (test_v2.py)

• test_run_sink_with_mixed_literal_and_dynamic_registration_tags (line 431)
  • Verifies the dataset upload block receives correctly resolved mixed array at runtime
• test_manifest_parsing_with_mixed_literal_and_selector_registration_tags (line 496)
  • Tests manifest parsing accepts mixed array with both $inputs and $steps selectors
• test_manifest_parsing_with_all_selector_types_in_registration_tags (line 543) - Case 3
  • Validates mixed literals and selectors pattern: ["literal", "$inputs.dynamic", "$steps.output.tag"]

Integration Tests (test_workflow_with_active_learning_sink.py)

• test_active_learning_workflow_with_custom_tag_value_resolves_correctly (line 182)
  • End-to-end test verifying workflow executes successfully with custom tag values in mixed array

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Requirement 2: Should Resolve Referenced Arrays (with Flattening)

Pattern: ["literal1", "$inputs.string_tag"] where string_tag = ["value1", "value2"] → ["literal1", "value1", "value2"]

Parameter Resolution Tests (test_step_input_assembler.py)

• test_unfold_parameters_when_array_element_resolves_to_array_and_should_flatten (line 534)
  • Tests selector resolving to array preserves nested structure at unfold layer (flattening occurs elsewhere)
• test_unfold_parameters_when_batched_array_element_resolves_to_arrays (line 568)
  • Tests batched selector where each batch element resolves to different arrays

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Requirement 3: Should Resolve Literal Strings in Array (Baseline)

Pattern: ["literal1", "A string"] → ["literal1", "A string"]

Schema Parsing Tests (test_schema_parser.py)

• test_parse_block_manifest_when_manifest_defines_only_list_of_strings (line 706)
  • Verifies baseline case with only literal strings creates primitive type definition without selectors

Block-Level Tests (test_v2.py)

• test_manifest_parsing_with_all_selector_types_in_registration_tags (line 543) - Case 1
  • Validates manifest parsing for array containing only literal strings: ["tag1", "tag2", "tag3"]

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Requirement 4: Should Resolve Just String

Pattern: reference_tags = "literal1" → ["literal1"]

Schema Parsing Tests (test_schema_parser.py)

• test_parse_block_manifest_when_manifest_defines_union_of_string_and_string_selector (line 591)
  • Tests schema parsing for non-array union accepting either string or selector

Block-Level Tests (test_v2.py)

• test_manifest_parsing_with_all_selector_types_in_registration_tags (line 543) - Cases 1-3
  • Implicitly validates that both string and array formats are accepted by the manifest

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Requirement 5: Should Resolve Just Selector That's an Array

Pattern: reference_tags = $inputs.string_tag where string_tag = ["value1", "value2"] → ["value1", "value2"]

Schema Parsing Tests (test_schema_parser.py)

• test_parse_block_manifest_when_manifest_defines_list_of_strings_and_list_selector (line 647)
  • Tests Union[List[str], WorkflowParameterSelector] where entire parameter can be selector to array
• test_parse_block_manifest_when_manifest_defines_only_string_selector_list (line 745)
  • Tests array containing only selectors (no literals): List[WorkflowParameterSelector(STRING_KIND)]

Parameter Resolution Tests (test_step_input_assembler.py)

• test_unfold_parameters_when_array_has_only_dynamic_selectors (line 419)
  • Tests array with only dynamic selectors are all properly resolved

Block-Level Tests (test_v2.py)

• test_manifest_parsing_when_registration_tags_given_as_selector (line 158)
  • Tests entire registration_tags parameter as single selector: "$inputs.tags"
• test_manifest_parsing_with_all_selector_types_in_registration_tags (line 543) - Case 2
  • Validates single selector reference pattern: "$inputs.tags"