`add_well_keyword_event` previously emitted items in `keyword_data` dict
insertion order. Eclipse keywords such as WCONHIST are positional, so a
non-canonical order silently corrupted the simulator input.
`RifEventKeywordFormatter::formatKeyword` now walks the OPM
`ParserRecord` schema and emits items in canonical order, inserting
`1*` defaults for intermediate gaps and dropping trailing unspecified
items. Items that are not part of the keyword schema (e.g. mnemonic-list
keywords like RPTRST/RPTSCHED) are appended after the canonical block in
caller-supplied order to preserve existing behaviour.
Fixes#14065.