Add pc 1.9.1 data and real 1.9.4 language table

[milutinke]

Split out of #1287.

1.9.1 was only a pre2 stub. This completes the entry and adds its language file (2855 keys, byte-exact against vanilla en_us). It also adds the real 1.9.4 table and points 1.9.2, 1.9.4, 16w20a and 1.10-pre1 at the right files. Heads up: the existing 1.9 language file looks like the 1.9.4 table minus two keys, I left that file alone.

Full mocha suite passes (2051 passing, 0 failing).

[rom1504]

Astra agent review — AI-generated, not manually written by the maintainer.

The new release entry is useful, but the schema copy introduces a public representation regression. Please preserve the existing symbolic enums before landing; the dimension-width and language corrections can remain. The inline finding comes from the full schema comparison performed earlier today at this unchanged head, with current discussion rechecked.

Skills used: prismarine-review checked the current revision and discussion; prismarine-protocol-data-review checked the version-selected producer/consumer contract; prismarine-architecture-review checked package ownership and integration scope.

[rom1504]

Astra agent review — AI-generated, not manually written by the maintainer.

Please retain the normalized mapper here and in entity_action, difficulty, and game_state_change, then regenerate protocol.json. Compared with the existing 1.9 schema, this new 1.9.1 copy changes those four fields back to numeric primitives, in addition to the intended login.dimension width change. For example, callers writing client_command with the established symbolic request_stats value no longer pass through a mapper to its ordinal; decoded values also change shape only on this patch version. A wire-compatible version copy should preserve the symbolic API. Check named and numeric writes through the production compiled serializer after restoring the mappings.

Skills used: prismarine-review checked the current revision and discussion; prismarine-protocol-data-review checked the version-selected producer/consumer contract; prismarine-architecture-review checked package ownership and integration scope.

[milutinke]

Good catch, fixed. The 1.9.1 proto was copied from 1.9 with four mappers flattened to primitives: client_command, entity_action, difficulty and game_state_change. I restored all four from the 1.9 schema (ordinals untouched, so wire compatible) and regenerated protocol.json with the repo build script.

The proto diff against 1.9 is now just the version tag and the intended login dimension width change. Full suite passes (2051 passing, 0 failing), including the proto sync check.