feat(experiments): Update metadata shape and add filter support

[shanaiabuggy]

Updates Experiment.metadata and ExperimentGroup.metadata type to be dict[str, str] and adds filter support.

Summary by CodeRabbit

• New Features

  • Added metadata key/value filtering for experiment and experiment-group listings.
  • Documented rollup metric range filter examples for experiment searches.

• Improvements

  • Standardized experiment metadata values as strings across requests, responses, and stored records.
  • Preserved compatibility with existing metadata by converting legacy non-string values during deserialization.

• Tests

  • Added coverage for metadata filtering and legacy metadata conversion.

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📥 Commits

Reviewing files that changed from the base of the PR and between 275c8cd and b38c155.

⛔ Files ignored due to path filters (17)

• sdk/python/nemo-platform/.nmpcontext/openapi.yaml is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/resources/experiment_groups/experiment_groups.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/resources/experiments/experiments.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiment_groups/experiment_group_create_params.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiment_groups/experiment_group_filter_param.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiment_groups/experiment_group_list_params.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiment_groups/experiment_group_response.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiment_groups/experiment_group_update_params.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiments/experiment_create_params.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiments/experiment_filter_param.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiments/experiment_list_params.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiments/experiment_response.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/experiments/experiment_update_params.py is excluded by !sdk/**
• sdk/python/nemo-platform/src/nemo_platform/types/intake/ingest/atif_trajectory_param.py is excluded by !sdk/**
• sdk/python/nemo-platform/tests/api_resources/intake/ingest/test_atif.py is excluded by !sdk/**
• sdk/python/nemo-platform/tests/api_resources/test_experiment_groups.py is excluded by !sdk/**
• sdk/python/nemo-platform/tests/api_resources/test_experiments.py is excluded by !sdk/**

📒 Files selected for processing (8)

• openapi/ga/individual/platform.openapi.yaml
• openapi/ga/openapi.yaml
• openapi/openapi.yaml
• services/intake/src/nmp/intake/api/v2/experiments/endpoints.py
• services/intake/src/nmp/intake/api/v2/experiments/schemas.py
• services/intake/src/nmp/intake/entities/experiments.py
• services/intake/tests/test_experiment_default_sort.py
• services/intake/tests/test_experiment_optimization_fields.py

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📝 Walkthrough

Walkthrough

Experiment and experiment-group metadata now uses string-valued schemas, supports metadata key/value list filters, preserves legacy deserialization through coercion, and adds coverage for filtering and metadata conversion.

Changes

Experiment Metadata Filtering

Layer / File(s)	Summary
API filtering contracts and documentation openapi/.../platform.openapi.yaml, openapi/ga/openapi.yaml, openapi/openapi.yaml, services/intake/.../experiments/endpoints.py	OpenAPI schemas and list endpoint descriptions document metadata filters and constrain metadata values to strings.
Typed metadata schemas and coercion services/intake/.../experiments/schemas.py, services/intake/.../entities/experiments.py	Request, response, filter, and entity models use string-valued metadata; legacy non-string values are JSON-stringified during validation.
Metadata coercion and filtering tests services/intake/tests/test_experiment_default_sort.py, services/intake/tests/test_experiment_optimization_fields.py	Tests cover legacy metadata conversion and metadata filtering for experiments and experiment groups.

Suggested reviewers: briannewsom, jashg, mckornfield, benmccown, aray12

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 11.11% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	Title accurately summarizes the main change: metadata type tightening and new filter support for experiments.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch sbuggy/ase-457

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[github-actions]

Suite	Lines Covered	Line Rate	Branch Rate
Unit Tests	23845/31009	76.9%	61.7%
Integration Tests	13817/29658	46.6%	19.6%