feat: add watchOS and visionOS OpenMedKit targets

[maziyarpanahi]

Pull Request

Description

Adds native watchOS and visionOS support to OpenMedKit while keeping constrained platforms on a fail-closed Nano model budget. The prior package targets and runtime dependency graph only supported iOS and macOS, so watchOS and visionOS could neither build the package nor enforce platform-appropriate model limits.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code refactoring
• Performance improvement
• Test addition/improvement

Changes Made

• Add watchOS 10 and visionOS 1 package targets with conditional full-runtime dependencies.
• Add platform-aware Nano/Tiny/Base model selection, memory and parameter ceilings, INT8 enforcement, and constrained model loading.
• Add synthetic redaction parity coverage and simulator CI jobs for watchOS and visionOS.
• Document platform support, deployment targets, model budgets, and constrained loading.

Testing

• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have tested this change with different models/inputs

Validation completed:

• .venv/bin/python -m pytest tests/ -q — 5,186 passed, 55 skipped
• arch -arm64 swift test — 68 tests executed, 14 skipped, no failures
• Focused watchOS simulator parity tests
• visionOS simulator-target cross-build
• Generic iOS simulator build
• make format-swift
• make lint-swift
• make docs-build
• Scoped pre-commit checks
• Workflow syntax validation

Documentation

• I have updated the documentation accordingly
• I have added docstrings to new functions/classes
• I have updated the CHANGELOG.md

Code Quality

• I ran make format, make lint, and make format-check
• For Swift/OpenMedKit changes, I ran make format-swift and make lint-swift
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings

Python formatting commands are not applicable because this change does not modify Python sources.

Dependencies

• I have not added any new dependencies
• OR I have added new dependencies and they are justified because: ____

Checklist

• I have read the contributing guidelines
• My commits have clear, descriptive messages
• I have squashed/organized my commits appropriately

Related Issues

Closes #955

Screenshots/Examples

The parity test redacts the synthetic note Patient Ada Lovelace, MRN TEST-123, called 555-0100. consistently across the supported constrained platforms.