family member container parameter fix

[ctreffs]

Description

This PR refines the Parameter Pack implementation by addressing naming inconsistencies and shadowing issues in FamilyMemberContainer. It also marks the completion of the parameter_packs_20260213 track.

Rationale:

• Unify the API for FamilyMemberContainer to use plural components: for all initializers.
• Resolve shadowing of the components property which caused build failures when swiftformat removed explicit self. prefixes.

Detailed Design

Updated FamilyMemberContainer initializers:

public struct FamilyMemberContainer<each C: Component> {
    public let components: [(repeat each C)]

    public init(components: (repeat each C)...) { ... }

    // Renamed internal parameter to 'sequence' to avoid shadowing 'components'
    public init<S>(components sequence: S) where S: Sequence, S.Element == (repeat each C) {
        components = Array(sequence)
    }

    // Renamed internal parameter to 'iterator' to avoid shadowing 'components'
    public init(components iterator: Family<repeat each C>.ComponentsIterator) {
        components = Array(iterator)
    }
}

Documentation

• Updated symbol-level documentation for FamilyMemberContainer initializers.
• Documentation follows existing DocC standards.

Testing

• Verified with FamilyCodingTests.swift.
• All 138 tests in the suite passed.
• Ran make pre-commit to ensure linting and formatting are correct.

Performance

• No performance impact expected as these are naming and shadowing fixes in the coding layer.

Source Impact

• Minor source-breaking change for anyone using the (previously singular) component: parameter name in the sequence initializer. However, this aligns it with the rest of the API.

Checklist

• I've read the Contribution Guidelines
• I've followed the coding style of the rest of the project.
• I've added tests covering all new code paths my change adds to the project (to the extent possible).
• I've added benchmarks covering new functionality (if appropriate).
• I've verified that my change does not break any existing tests or introduce unexpected benchmark regressions.
• I've updated the documentation (if appropriate).