refactor(simulation): strip archetype trace + HeritageRoot per cascade (#877, #878)

Sprint 37 dead-code sweep closing out two stale supersession chains:

#877 (D-167, 2026-03-24): Removes HeritageRoot type alias and
ZonePaletteModifier::Heritage variant from server/src/simulation/
generator.rs. The 7 abstract heritage roots were retired in favour of
the corridor cultural system; these two stubs were the only remaining
references.

#878 (D-032 + cascade rule): Strips the entire CharacterArchetype
(Smuggler/Detective) trace from the server. Per lead direction
2026-04-21 and the development cascade (CLAUDE.md), character/NPC/
verb-differentiation/monologue code is Phase 6 detail that should
not exist in code yet. The running archetype trace was pre-cascade
filler, not production — production is only the client's character-
creation UI and insert screens (client follow-up in #882).

Deleted:
- CharacterArchetype enum + StartupMessage.character_archetype field
- archetype_verb_label() + archetype branch of apply_phase2_verb_filter
  (D-057 character-verb differentiation — marked superseded)
- MonologueState.character partitioning
- Gauntlet archetype plumbing (setup_gauntlet no longer takes an archetype)
- server/content/schemas/drama_module.schema.yaml (zero Rust consumers)
- server/content/modules/tier1/smuggling_ring_v0_1.yaml
- server/tests/archetype_monologue.rs (regression guard for the removed system)
- server/tests/v01_integration_playthrough.rs (archetype-dependent)

Decision updates:
- decisions/content.md D-032 supersession rewritten to cite the cascade
  (v0.2 drop invalidated the prior D-117 framing).
- decisions/content.md D-035 tag taxonomy: `character` enum footnote
  updated; field noted as unused, do not reintroduce without a
  confirmed Phase 6 design.
- decisions/perception.md D-057: archetype-verb differentiation marked
  superseded.

Also bundles the types.rs version-field removal from #874 since the
file was already touched here.

Full trace audit in docs/architecture/sprint-37-878-audit.md.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/tests/game_loop.rs

@@ -68,7 +68,6 @@ fn player_moves_north_through_full_pipeline() {
         rmp_serde::from_slice(&response).expect("deserialize snapshot");
 
     // Snapshot captures state at end of tick 0 (before advance_tick increments to 1)
-    assert_eq!(snapshot.version, PROTOCOL_VERSION);
     assert_eq!(snapshot.tick, 0);
     assert_eq!(snapshot.entities.len(), 1);