## Summary

Now that bumpalo has been inlined into oxc_allocator (#18168), this PR cleans up comments and documentation that still reference bumpalo as an external dependency.

- Update module docs in `bump.rs` and `bumpalo_alloc.rs` to say "originally derived from" instead of "ported from"
- Remove obsolete comments about bumpalo version pinning in `from_raw_parts.rs`
- Update inline comments in `allocator.rs` from "delegates to bumpalo" to "it's a small function"
- Remove outdated TODO about replacing bumpalo in `tracking.rs`
- Update `ARCHITECTURE.md` and parser docs to reference `oxc_allocator` instead of bumpalo
- Clean up bumpalo references in other crates (`oxc_semantic`, `oxc_data_structures`, `apps/oxlint`, `napi/parser`, `tasks/ast_tools`)

## Test plan

- [x] `cargo check -p oxc_allocator` passes
- [x] `cargo test -p oxc_allocator` passes
- [x] Changes are documentation/comment only - no functional changes

🤖 Generated with [Claude Code](https://claude.ai/code)

#18168 copied `bumpalo`'s code for `Bump` into `oxc_allocator` crate.
#18172, #18181, and #18234 made a few improvements to the
implementation.

However, #18168 removed various things, and altered others. Notably, it
removed the`MIN_ALIGN` generic param, which we definitely want to keep.

I'm going to be working on the allocator, and would like to start with a
clean slate, beginning with the "known good" implementation of
`bumpalo`.

This PR removes the previous modified `bumpalo` implementation, and
copies latest version of `bumpalo` from main branch into the repo. It
then makes the absolute minimum changes necessary just to make CI pass.

Note: Unlike #18168, this PR keeps all the doctests for `Bump`, using a
trick of adding the crate to it's own `dev-dependencies` with `testing`
feature enabled, and exposing `Bump` only with that feature.

This PR is broken into multiple commits, so we have an exact "trail of
breadcrumbs" of how we've diverged from `bumpalo`. I intend to manually
merge this PR, so that record remains on Github (instead of Graphite
squashing all the commits).

Later PRs in this stack reapply the changes made in #18172, #18181, and
#18234 on top of the fresh base implementation. This PR is a small perf
regression, but that will be won back once those other changes are
reapplied.

Follow on after #18172.

That PR made changes to comments to remove references to `bumpalo` from the codebase. Correct a few of those comments which were incorrect.