feat(simulation): ban HashMap via clippy disallowed_types, fix violations (#343)

Adds server/.clippy.toml with disallowed-types for std::collections::HashMap
and std::collections::HashSet. HashMap iteration order is non-deterministic
and breaks deterministic simulation replay (D-030).

Changes:
- server/.clippy.toml: disallow HashMap and HashSet crate-wide
- simulation/movement.rs: WalkabilityMap.chunks and occupied map → BTreeMap;
  add PartialOrd+Ord to ChunkCoord, TilePosition, TilePresence
- simulation/monologue.rs: MonologueState.shown_ids → BTreeSet (simulation state)
- perception/shadowcast.rs: #![allow] — per-frame FOV scratch, iteration irrelevant
- perception/interpretation.rs: #![allow] — per-frame lookup table, key-only access
- perception/query.rs: #![allow] — sector_lookup is a per-frame read-only cache

Also applies cargo fmt to pre-existing format drift in contraband.rs,
dialogue.rs, test_world/mod.rs, and several integration tests.

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

server/src/simulation/movement.rs

@@ -23,7 +23,17 @@ pub struct PlayerCharacter;
 /// Examples: a Standing character can walk past a Seated NPC at a console,
 /// a Fixture (terminal) shares a tile with someone Seated at it.
 #[derive(
-    Component, Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord, Default, Serialize,
+    Component,
+    Debug,
+    Clone,
+    Copy,
+    PartialEq,
+    Eq,
+    Hash,
+    PartialOrd,
+    Ord,
+    Default,
+    Serialize,
     Deserialize,
 )]
 pub enum TilePresence {
@@ -42,7 +52,9 @@ pub enum TilePresence {
 /// Tile position component for grid-based movement.
 /// Discrete integer coordinates used in simulation; converted to f32
 /// at the bridge boundary for VisibleEntity wire format.
-#[derive(Component, Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord, Serialize, Deserialize)]
+#[derive(
+    Component, Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord, Serialize, Deserialize,
+)]
 pub struct TilePosition {
     pub x: i32,
     pub y: i32,