fix(apple): keep the documented terminating process, parent pid and metadata members of IPS reports (#7079)

Apple's crash report JSON documents termination.byPid, byProc and flags, the body's parentPid, and
the metadata line's build_version and platform. The parser shapes did not list them, so they were
reported only by name in unlisted_keys / unlisted_body_keys and their values were dropped: a
watchdog kill no longer said which process ended it, and process kept parentProc without its pid.
#4297 asks for termination members beyond namespace/code/indicator to be retained as recorded, and
docs/apple-ips.md says documented fields are reproduced.

They are now kept: termination.by_proc, termination.by_pid and termination.flags, process.parent_pid
and metadata.build_version / metadata.platform. The integers are recorded integers, so they count
toward max_integer_text_bytes and a type mismatch is recorded like the other fields.

docs/apple-ips.md

@@ -31,7 +31,10 @@ stackshots, return no crash result.
 `process`, `exception`, `termination`, `faulting_thread`, `threads`, and
 `images` reproduce documented body fields when present, including each image's
 `name` and each frame's `symbolLocation` (as `symbol_location`, the byte offset
-from the start of `recorded_symbol`). Integers keep their
+from the start of `recorded_symbol`). `termination` keeps the terminating
+process as `by_proc` and `by_pid` and its `flags`; `process.parent_pid` keeps
+`parentPid` next to `parent`; and `metadata` keeps `build_version` and
+`platform`. Integers keep their
 decimal literals and a hexadecimal form, including arm64e registers above
 2^53. Frame roles follow the recorded frame index: row zero of the resolved
 faulting thread is `faulting_instruction`, row zero of other threads is