Spread control: client-seed no-spread

HL2's CBaseEntity::FireBullets seeds its RNG from the usercmd random_seed
(m_bUseServerRandomSeed is false for HL2 weapons), so the client can select the
8-bit seed that puts CShotManipulator::ApplySpread closest to the center.

- New feature Spread control -> Active / No spread (both default on).
- Precompute the best seed for a single shot and for the shotgun's 8-shot
  primary (first pellet accurate) and 12-shot secondary windows using the
  engine's own RandomSeed/RandomFloat from libvstdlib.
- Set cmd->random_seed on attack commands; note_modified repairs the CRC.
- The random cone offset is neutralized, but the cone size, the pistol
  accuracy penalty, server view punch and any damage falloff remain
  server-side; stock HL2 has no distance damage falloff.

1 files changed, 28 insertions, 2 deletions

diff --git a/CONTEXT.md b/CONTEXT.md
index 8fb2197..861fbf8 100644
--- a/CONTEXT.md
+++ b/CONTEXT.md
@@ -111,6 +111,9 @@ HL2hake
     Assist timing
   Melee killbot
     Active
+  Spread control
+    Active
+    No spread
   ESP
     Active
     Show neutral / healthbar / healthnum / name / skeleton / box / speed graph
@@ -186,6 +189,27 @@ Binds use SDL scancodes; mouse buttons are pseudo-scancodes 600..604.
 - Vischeck uses the shared `MASK_VISIBLE`/world-only path (static props are
   ignored).
 
+## Spread control
+
+- HL2's `CBaseEntity::FireBullets` seeds its RNG from
+  `CBaseEntity::GetPredictionRandomSeed(info.m_bUseServerRandomSeed)`; HL2
+  weapons leave `m_bUseServerRandomSeed` false, so the server uses the
+  client usercmd's `random_seed` (masked to 8 bits). This is the TF2-style
+  client-side seed hook.
+- `Spread control -> No spread` precomputes, with the engine's own
+  `RandomSeed`/`RandomFloat`, the 8-bit seed whose
+  `CShotManipulator::ApplySpread` offset is smallest. It sets
+  `cmd->random_seed` on attack commands; `note_modified` repairs the CRC.
+- Shotguns use consecutive seeds per pellet. The primary's first pellet is
+  `FIRE_BULLETS_FIRST_SHOT_ACCURATE`, so the table excludes it; the secondary
+  uses all 12. Separate best starting seeds are precomputed for 1, 8 and 12
+  pellets.
+- This attacks the random cone offset only. The cone size, the pistol's
+  `m_flAccuracyPenalty` growth, the server view punch added to
+  `GetAutoaimVector`, and any damage falloff are server-side state. In
+  single-player those can be written/hooked locally; stock HL2 has no
+  distance damage falloff.
+
 ## Jumpbug
 
 - Automatic while falling when the predicted landing speed
@@ -237,6 +261,8 @@ Binds use SDL scancodes; mouse buttons are pseudo-scancodes 600..604.
 
 - **GUI**: replace/augment the VGUI ISurface menu with an immediate-mode GUI
   (Dear ImGui or a custom implementation); needs a design grill first.
-- **Distance weapon spread thesis**: TBD — user will explain. Likely models
-  weapon spread as a function of distance for aim/trigger decisions or visuals.
+- **Server-side spread/recoil control**: optional single-player writes to the
+  pistol accuracy penalty and view punch, and a true zero-cone hook if wanted.
+- **Distance weapon spread thesis**: addressed by Spread control; stock HL2
+  hitscan damage is range-independent, so distance efficiency is the cone.