docs(int64): add README

[rami3l]

Disclaimer: This PR was generated by an LLM agent as part of an experiment.

[peter-jerry-ye-code-review]

Binary representation section lacks explanation of byte order impact

Category
Maintainability
Code Snippet
test "binary conversion" {
let x = 258L // Int64 value of 258
let be_bytes = @int64.to_be_bytes(x)
let le_bytes = @int64.to_le_bytes(x)
Recommendation
Add explanatory text about when to use big-endian vs little-endian, e.g.: 'Big-endian (be_bytes) is commonly used for network protocols, while little-endian (le_bytes) matches the byte order of most modern processors.'
Reasoning
Documentation should not just show how to use functions but also guide users on when to use different options. This helps developers make informed decisions.

Missing examples of arithmetic operations

Category
Maintainability
Code Snippet
test "basic operations" {
let i : Int64 = -12345L // Int64 literal
// You can also convert from an Int like so:
inspect!(@int64.from_int(-12345) == i, content="true")
Recommendation
Add examples of common arithmetic operations like addition, subtraction, multiplication, and division with Int64 values
Reasoning
Basic arithmetic operations are fundamental use cases that should be documented with examples to show proper usage and potential pitfalls

Hash trait implementation mention lacks example

Category
Maintainability
Code Snippet
Note that Int64 implements the Hash trait, allowing it to be used as keys in hash maps and members of hash sets.
Recommendation
Add a concrete example showing Int64 being used as a key in a hash map or as a member of a hash set
Reasoning
When documenting important features like trait implementations, concrete examples help users understand the practical applications

[coveralls]

Pull Request Test Coverage Report for Build 5982

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 92.365%

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Totals
Change from base Build 5981:	0.0%
Covered Lines:	5625
Relevant Lines:	6090

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💛 - Coveralls