fix(simulation): PR #66 review — dedup vision, spawn components, doc fixes

- vision.rs: deduplicate own-tile entity iteration, add same-tile test
- spawn.rs: add NpcVisionState, NpcMemory, PlayerAwareness to content-
  spawned NPCs (matching generate_npc)
- pressure.rs: update who_knows_full_scan doc to reflect actual call
  frequency, document O(N) acceptability at call site
- types.rs: fix stale protocol version comment (13→14)
- generate.rs: format!() → .to_string() (clippy)
- vision.rs: hardcoded 10 → TICKS_PER_GAME_MINUTE
- relationships.rs: fix comment "15%" → "20%" to match code
- pressure.rs: document total() floor-truncation
- save_state.rs: document NpcMemory exclusion as intentional

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

server/src/simulation/save_state.rs

@@ -31,6 +31,8 @@
 //! - Full ECS world extraction/injection (system not yet written)
 //! - Pathfinding state (reconstructed from position + routine)
 //! - Tier transitions in-flight (dropped to background state on load)
+//! - `NpcMemory` (intentionally excluded — stale inferences would be wrong after
+//!   reload; memory degrades naturally over time so reset-on-load is acceptable)
 
 use serde::{Deserialize, Serialize};