1. 1. Summary

Guarantees the server-side JavaScript engine is never compiled into PPC (`ppc64le`)
`mongod`/`mongos` binaries, enforced in the build graph rather than per-variant flags.
PPC is the only platform still on the legacy/native mozjs engine (the WASM engine is
unsupported on ppc64le), which motivated dropping server-side JS there (see BF-44837).

`mongod_main` and `mongos_main` select their scripting backend on the new
`server_js_enabled_and_not_ppc` config group (`server_js_enabled` *and* `not_ppc`).
On ppc64le that condition can never match, so any ppc64le build links `scripting_none`
instead of `scripting_server` — **regardless of the `server_js` flag or which pipeline
builds it**. This makes it impossible to accidentally ship a PPC release with the JS
engine compiled in.

The test shell keeps its own JS engine, so resmoke jstests still run on PPC. Tests that
require server-side scripting are excluded via the existing `requires_scripting` tag.

1. 1. Changes

• `bazel/config/BUILD.bazel` — add the `server_js_enabled_and_not_ppc` config setting
  group (`server_js_enabled` + `not_ppc`).
• `src/mongo/db/BUILD.bazel`, `src/mongo/s/BUILD.bazel` — point the `mongod_main` /
  `mongos_main` scripting `select` at `server_js_enabled_and_not_ppc`, so ppc64le links
  `scripting_none`.
• `etc/evergreen_yml_components/variants/ibm/test_release.yml` — add `requires_scripting`
  to the 3 base PPC variants' `--excludeWithAnyTags` (RHEL 8.1 / 9 / 10; inherited by the
  `-dynamic` variants).
• `etc/evergreen_yml_components/variants/amazon/test_dev_master_branch_only.yml` — add
  `requires_scripting` to the nightly `rhel81-ppc64le-bazel-compile` smoke check.

1. 1. Safety / scope

• The scripting change is gated on `not_ppc`, so *all non-PPC platforms are unchanged* —
  they still honor `--server_js` (default `True`).
• The guarantee holds for the shipped release artifacts (the base PPC variants with
  `has_packages`/`push_*`), independent of any Evergreen build flag.
• jstests continue to run on PPC; only `requires_scripting`-tagged tests are skipped.

1. 1. Testing

Evergreen patches on the PPC variants (linked in comments). The `rhel81-ppc64le-bazel-compile`
smoke check builds cleanly with server-side JS compiled out.