Add Deref/DerefMut support for all memory abstractions

[uselessgoddess]

Summary

Implements Deref<Target=[T]> and DerefMut for all memory types (Alloc, FileMapped, Global, System, TempFile), enabling safe slice-based access through standard Rust indexing, slicing, and iteration — while preserving full backward compatibility with allocated()/allocated_mut().

What changed

• Alloc<T, A> and FileMapped<T>: Added Deref/DerefMut impls; allocated()/allocated_mut() now delegate to deref
• delegate_memory! macro: Generates Deref/DerefMut impls for Global, System, TempFile wrappers
• 22 new tests in 4 categorized files covering indexing, slice methods, consistency, and all types

What users can now do

use platform_mem::{Global, RawMem};

let mut mem = Global::<u64>::new();
mem.grow_from_slice(&[3, 1, 4, 1, 5]).unwrap();

// Indexing and slicing — no unsafe, no .allocated() needed
assert_eq!(mem[0], 3);
assert_eq!(&mem[1..4], &[1, 4, 1]);

// All slice methods work via Deref
mem.sort();
assert_eq!(&mem[..], &[1, 1, 3, 4, 5]);

// Backward compatible — allocated() still works
assert_eq!(mem.allocated(), &[1, 1, 3, 4, 5]);

Backward compatibility

• allocated()/allocated_mut() remain on the RawMem trait and work unchanged
• ErasedMem and Box<dyn ErasedMem> continue to work unchanged
• tests/coverage.rs is unmodified — all 72 existing coverage tests pass as-is
• No existing features removed

Test organization

Deref tests are split into 4 categorized files in tests/:

• deref_indexing.rs — element access, ranges ([i], [1..4], [2..], [..3], [..], [1..=3]), empty deref
• deref_slice_methods.rs — len(), is_empty(), iter(), iter_mut(), contains(), sort()
• deref_consistency.rs — Deref/allocated() API equivalence, grow/shrink behavior
• deref_all_types.rs — coverage for Global, System, TempFile, Alloc, FileMapped

Diff minimization

The src diff is purely additive where possible:

• alloc.rs: +18 lines (Deref/DerefMut impls added, allocated() delegates to self)
• file_mapped.rs: +18 lines (same pattern)
• lib.rs: +15 lines (Deref/DerefMut added to macro, existing delegation unchanged)

Test plan

• All existing tests pass (cargo test --all-features — 114 tests)
• 22 new Deref-specific tests in 4 categorized files
• Tests verify consistency between Deref and allocated() APIs
• No new clippy warnings introduced
• tests/coverage.rs unchanged from main

🤖 Generated with Claude Code

Fixes #18

[konard]

May be we somehow can make common trait that will support both allocated/allocated_mut and Deref, so we can actually compare them using a benchmark?

[konard]

Conflicts should be resolved.

We should support Deref in addition to existing logic for backward compatibility. And support if for all abstractions we have, so nothing breaks, but we have ability to have safer abstraction for users of the library.

So that as I understand should allow us to use regular indexes and slices and ranges, instead of unsafe raw pointers.

We need to ensure all changes are correct, consistent, validated, tested, logged and fully meet each and all discussed requirements (check issue description and all comments in issue and in pull request). Ensure all CI/CD checks pass.

[konard]

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[konard]

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[konard]

✅ Ready to merge

This pull request is now ready to be merged:

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[konard]

Please try to organize code in such a way that git diff is smaller for easier review. And double check we put all tests out of src folder into tests folder. No previous features are removed or missing, only new Deref feature is added. And also we have 100% tests coverage and all tests file are split into categories. Not all tests in single file.

We need to ensure all changes are correct, consistent, validated, tested, logged and fully meet each and all discussed requirements (check issue description and all comments in issue and in pull request). Ensure all CI/CD checks pass.

[konard]

🤖 AI Work Session Started

Starting automated work session at 2026-04-10T22:38:52.268Z

The PR has been converted to draft mode while work is in progress.

This comment marks the beginning of an AI work session. Please wait for the session to finish, and provide your feedback.

[konard]

🤖 Solution Draft Log

This log file contains the complete execution trace of the AI solution draft process.

💰 Cost: $2.235564

📊 Context and tokens usage:

• Context window: 74.1K / 1M (7%) input tokens, 15.6K / 128K (12%) output tokens

Total: (63.6K + 2.9M cached) input tokens, 15.6K output tokens, $2.235564 cost

🤖 Models used:

• Tool: Anthropic Claude Code
• Requested: opus
• Model: Claude Opus 4.6 (claude-opus-4-6)

📎 Log file uploaded as Gist (1052KB)

• View complete solution draft log

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Now working session is ended, feel free to review and add any feedback on the solution draft.

[konard]

✅ Ready to merge

This pull request is now ready to be merged:

• All CI checks have passed
• No merge conflicts
• No pending changes

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Monitored by hive-mind with --auto-restart-until-mergeable flag