Add time and space complexity documentation to all public Set module functions

[Copilot]

This PR adds comprehensive time and space complexity documentation to all public functions in the F# Set module, addressing the need for developers to understand the performance characteristics of Set operations.

Changes Made

Added <remarks> sections with time and space complexity information to:

• 32 Set module functions (Set.empty, Set.add, Set.contains, etc.)
• 10 Set type members (constructor, Add, Remove, Count, etc.)

Complexity Categories

The documentation categorizes operations by their algorithmic complexity:

• O(1): empty, singleton, isEmpty
• O(log n): add, contains, remove, minElement, maxElement
• O(n): count, fold, foldBack, iter, toList, toArray
• O(n log n): filter, map, partition, ofList, ofArray, ofSeq
• O(m log n): union, intersect, difference, subset operations

Implementation Details

The complexity analysis is derived from the actual Set implementation, which uses balanced binary trees (AVL-like) with the following characteristics:

• Height-balanced tree structure ensures O(log n) for basic operations
• Traversal operations are O(n) as they visit each element once
• Set operations like union/intersect are O(m log n) where elements from one set are added to/checked against another
• Construction operations are O(n log n) as they add n elements each taking O(log n)

Example

/// <summary>Returns a new set with an element added to the set.</summary>
/// <param name="value">The value to add.</param>
/// <param name="set">The input set.</param>
/// <returns>A new set containing <c>value</c>.</returns>
/// <remarks>Time complexity: O(log n). Space complexity: O(log n).</remarks>
val add: value: 'T -> set: Set<'T> -> Set<'T>

Testing

• All changes build successfully without errors
• No breaking changes to existing API
• Documentation follows consistent format throughout
• Complexity analysis verified against implementation details

This documentation will help developers make informed decisions about Set usage in performance-critical scenarios.

This pull request was created as a result of the following prompt from Copilot chat.

Add time and space complexity documentation in to all public functions in the Set module in set.fsi. Derive complexity from implementation, using strict format, and append to existing remarks if present.

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[github-actions]

❗ Release notes required

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Change path	Release notes path	Description
src/FSharp.Core	docs/release-notes/.FSharp.Core/10.0.100.md	No release notes found or release notes format is not correct

[T-Gro]

@copilot : Add release notes to the /docs file designated for FSharp.Core release notes going into v 10.