Rear-fire + look views (task #68): the pod's rear arsenal reconstructed

The user's tip ("some mechs actually do fire backward") checks out end to
end.  Binary ground truth [T1]:
- weapon+0x334 (attr 0x1B "RearFiring"): the ctor tests the MOUNT SEGMENT's
  page name for the marker 'b' (@0x511aa2, part_013.c:6913-6930) -- the back
  gun ports sitelbgunport/siterbgunport.  The old reading ("EXT in the
  weapon model name") was a double misread (wrong string, wrong name).
- mech+0x410 (attr id 50 "RearFiring"; the old `stateFlags` label): the ctor
  ORs every weapon's flag (part_012.c:10220) -- "carries a rear arsenal".
- The mapper's five-state LOOK machine (part_013.c:396-459): on a state
  change it re-aims the eyepoint (mech+0x360 = EyepointRotation -- consumed
  by DPLEyeRenderable, already live in the port) and re-arms each weapon's
  viewFireEnable(+0x3E0): FORWARD view = the non-rear weapons, LOOK-BACK
  (yaw pi + lookBackAngle pitch) = the REAR-mounted ones, side/down = none.
  +0x3E0 is the same flag the emitter's Loaded->Firing gate reads (the old
  `useConfiguredPip` label) -- pips and fire permission both follow the view.

Port: rearFiring derived from the mount segment name (BTWeaponMountIsRear);
mech rearFiring ORed in the roster pass (the old SubProxy::IsDerivedFrom
stub returned 0 -- that loop never ran; now bridged through
BTWeaponIsRearFiring, which also fixes the weaponRoster fill); the look
commit is LIVE (BTCommitLookState: eyepoint EulerAngles from the authored
per-mech look angles -- now real members, were Wword scratch parks -- +
per-weapon view enables); MissileLauncher/ProjectileWeapon FireWeapon gate
on viewFireEnable like the emitter; RearFiring attrs (mech + weapon) bind
real members.  Keyboard: HOLD 'V' = the pod's rear-view button.

Live-verified on the default blackhawk: ERMLaser_2 -> siterbgunport rear=1,
ERMLaser_3 -> sitelbgunport rear=1, PPCs/SRMs/torso mounts forward -- the
blackhawk authors TWO REAR LASERS (owens also has back ports).  [rearfire]
trace under BT_PROJ_LOG.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

game/reconstructed/mislanch.cpp

@@ -267,6 +267,12 @@ void MissileLauncher::FireWeapon()
 {
 	Check(this);
 
+	// (task #68) the view gate: a weapon disabled in the CURRENT look view
+	// (rear rack in the forward view, anything in a side view) does not fire
+	// -- the same +0x3E0 gate the emitter's Loaded->Firing transition reads.
+	if (!viewFireEnable)
+		return;
+
 	// THE FIRING HEAT (task #9): heatCostToFire RAW into the launcher's own
 	// pendingHeat (pre-scaled 1e7-unit resources: SRM6 = 5e7, LRM15 = 6.5e7)
 	// -- the binary's add @part_013.c:8744-8747, gated on the heatable check.