fix(client): address PR #78 review comments

- Widen world_seed entropy from u32 to full u64 by combining two randi()
  calls (Hoshe warning #1)
- Persist world_seed to save directory and restore on resume_game() so
  loaded sessions maintain D-010 deterministic replay (Tyre warning #2)
- Constrain EntanglementConfig intrigue range based on flat value so
  mundane_ratio stays within D-029 spec [45,55]% (both reviewers)
- Remove dead VIS_PERIPHERAL constant and _grow_bounds() method
- Update test_client_p1 peripheral test for forward-only simplification
- Fix misleading exp_fade shader comment (filter_nearest = hard step)

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

server/src/content/entanglement.rs

@@ -44,9 +44,13 @@ impl EntanglementConfig {
     pub fn from_rng(rng: &mut SimRng) -> Self {
         // Sample flat_ratio ∈ [25, 35] — step of 1%
         let flat: u8 = rng.rng.random_range(25u8..=35u8);
-        // Sample intrigue_ratio ∈ [15, 25] — step of 1%
-        let intrigue: u8 = rng.rng.random_range(15u8..=25u8);
-        // Mundane fills the remainder (ensures sum = 100)
+        // Constrain intrigue range so mundane = 100 - flat - intrigue stays in [45, 55].
+        // mundane ≥ 45 → intrigue ≤ 55 - flat; mundane ≤ 55 → intrigue ≥ 45 - flat.
+        // Intersect with D-029 base range [15, 25].
+        let intrigue_min: u8 = (45u8.saturating_sub(flat)).max(15);
+        let intrigue_max: u8 = (55u8.saturating_sub(flat)).min(25);
+        let intrigue: u8 = rng.rng.random_range(intrigue_min..=intrigue_max);
+        // Mundane fills the remainder (ensures sum = 100, stays in [45, 55])
         let mundane: u8 = 100 - flat - intrigue;
         Self {
             flat_ratio: flat,
@@ -178,24 +182,17 @@ mod tests {
     #[test]
     fn mundane_ratio_within_bounds() {
         // D-029: mundane ∈ [45, 55]%
-        // Derivation: flat ∈ [25,35], intrigue ∈ [15,25], mundane = 100 - flat - intrigue
-        // worst case: flat=35, intrigue=25 → mundane=40 (below 45!)
-        // CAVEAT: this reveals a potential spec inconsistency — if flat and intrigue
-        // are sampled independently, mundane can fall outside [45,55].
-        // Resolution options: (a) constrain sampling so mundane stays in range,
-        // (b) accept mundane range as derived. This test documents the actual range.
-        // TODO: coordinate with Tyre on intended sampling strategy.
+        // Achieved by constraining intrigue range based on flat value so that
+        // mundane = 100 - flat - intrigue always stays within spec bounds.
         for seed in 0u64..200 {
             let c = EntanglementConfig::from_seed(seed);
             assert!(
                 c.is_valid(),
-                "Seed {seed}: ratios must sum to 100 regardless of mundane derivation"
+                "Seed {seed}: ratios must sum to 100"
             );
-            // Derived mundane range: 100 - 35 - 25 = 40 minimum, 100 - 25 - 15 = 60 maximum
-            // Note: if spec requires strict [45,55], the sampling ranges must be tighter.
             assert!(
-                c.mundane_ratio >= 40 && c.mundane_ratio <= 60,
-                "Seed {seed}: mundane_ratio {} out of derived [40, 60] range",
+                c.mundane_ratio >= 45 && c.mundane_ratio <= 55,
+                "Seed {seed}: mundane_ratio {} out of D-029 [45, 55] bounds",
                 c.mundane_ratio
             );
         }