Implement LRU cache (#150)

[luodeb]

• feat: update dependencies and implement LRU cache

• add LRU cache implementation in core/src/lrucache.rs
• refactor memory management to use new LRU cache methods

• feat: remove uluru dependency from Cargo files

• feat: reorganize lrucache module import in lib.rs and mm.rs

Description

Implementation

Additional Context

[Copilot]

Pull request overview

This PR replaces the external uluru dependency with a custom LRU cache implementation to address licensing concerns (implied by the PR title "fix license"). The implementation provides equivalent functionality for caching ELF file entries in the memory management module.

Changes:

• Implemented a custom LruCache with doubly-linked list structure using array indices
• Migrated from uluru::LRUCache to the new LruCache in the memory management module
• Removed the uluru dependency from Cargo files and updated chrono to version 0.4.43

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
core/src/lrucache.rs	New custom LRU cache implementation with fixed-size array storage and intrusive linked list
core/src/mm.rs	Updated to use new LruCache API (access, put, peek_mru, items, flush methods)
core/src/lib.rs	Added lrucache module to the module tree
core/Cargo.toml	Removed uluru dependency
Cargo.lock	Removed uluru package and updated chrono to 0.4.43

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[Godones]

@luodeb My question is why we need to replace the uluru dependency? If it really needs to be reimplemented, it would be better to make it a separate crate.

[luodeb]

@luodeb My question is why we need to replace the uluru dependency? If it really needs to be reimplemented, it would be better to make it a separate crate.

The LICENSE used by uluru is "MPL-2.0," which is incompatible with StarryOS's "Apache-2.0" license.

[Godones]

Is it possible to use the lru crate, whose MIT license is compatible with Apache-2.0?

[luodeb]

Is it possible to use the lru crate, whose MIT license is compatible with Apache-2.0?

MIT is ok