* Define a generic allocator interface to enable static polymorphism for
allocators (see `GenericAllocator` in `src/allocators.zig`). Note that
`std.mem.Allocator` itself is considered a generic allocator.
* Add utilities to `bun.allocators` for working with generic allocators.
* Add a new namespace, `bun.memory`, with basic utilities for working
with memory and objects (`create`, `destroy`, `initDefault`, `deinit`).
* Add `bun.DefaultAllocator`, a zero-sized generic allocator type whose
`allocator` method simply returns `bun.default_allocator`.
* Implement the generic allocator interface in `AllocationScope` and
`MimallocArena`.
* Improve `bun.threading.GuardedValue` (now `bun.threading.Guarded`).
* Improve `bun.safety.AllocPtr` (now `bun.safety.CheckedAllocator`).
(For internal tracking: fixes STAB-1085, STAB-1086, STAB-1087,
STAB-1088, STAB-1089, STAB-1090, STAB-1091)
### What does this PR do?
The DevSever's `IncrementalGraph` uses a data-oriented design memory
management style, storing data in lists and using indices instead of
pointers.
In conventional memory management, when we free a pointer and
accidentally use it will trip up asan. Obviously this doesn't apply when
using lists and indices, so this PR adds a check in debug & asan builds.
Everytime we free an `Edge` we better make sure that there are no more
dangling references to that spot.
This caught a case where we weren't setting `g.first_import[file_index]
= .none` when deleting a file's imports, causing a dangling reference
and out of bounds access.
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Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
