feat(camera): comprehensive camera system (C1)

Rebuild the camera around a single persistent MainCamera and the
Camera System design-doc model: two framing modes (Orbit = inspection/
docked tactical, Follow = track the ship) plus Cinematic as a boolean
overlay (free rotation + HUD hide + live gameplay), not a third mode.

Critical fixes (gap analysis A1-A3):
- A1: scenes now *reconfigure* the one startup camera instead of spawning
  a second one; despawn_in_system_scene no longer destroys MainCamera, so
  the session never loses its camera. .single_mut() on MainCamera now
  succeeds during flight.
- A2: Cinematic is a real overlay — toggle (KeyC), free-look rotation in
  any framing, HUD hidden while active, gameplay keeps running.
- A3: removed dead FollowCamera component + setup_follow_camera; tracking
  is unified in track_camera_target.

Gaps B1-B6:
- B1: adopted doc model (Cinematic overlay, not exclusive mode).
- B2: canonical isometric tactical_rotation() baseline.
- B3: smooth reframing via OrbitFocusGoal exponential-damp tween.
- B4: non-zero CameraState defaults.
- B5: consolidated the three orbit-control impls into one (dropped the
  starting_base local control + its Euler variant).
- B6: track_camera_target keeps OrbitCamera.target synced to the focus
  entity every frame.

Docked view now frames the actual station at a tactical iso distance.
cargo check + clippy clean for all newly-authored code; net -10 lines
(more dead code removed than added). 42 tests pass.

apps/game/src/gameplay/in_system/flight.rs

@@ -8,7 +8,7 @@
 
 use bevy::prelude::*;
 
-use crate::camera::{CameraState, CameraMode};
+use crate::camera::{CameraState, CameraMode, OrbitFocusGoal};
 use crate::gameplay::movement::components::{Velocity, MoveTarget};
 use crate::gameplay::galaxy::Identifiable;
 use super::{DockedState, UndockEvent};
@@ -53,14 +53,15 @@ fn handle_undock(
     mut events: EventReader<UndockEvent>,
     mut docked_state: ResMut<DockedState>,
     mut camera_state: ResMut<CameraState>,
-    player_query: Query<(Entity, &Transform), (With<PlayerShip>, With<Docked>)>,
+    mut focus_goal: ResMut<OrbitFocusGoal>,
+    player_query: Query<Entity, (With<PlayerShip>, With<Docked>)>,
     // docked_ui_query removed - UI no longer needed
 ) {
     for event in events.read() {
         bevy::log::info!("Handling undock from station {:?}", event.station_entity);
 
         // Find player ship
-        let Ok((player_entity, ship_transform)) = player_query.single() else {
+        let Ok(player_entity) = player_query.single() else {
             bevy::log::warn!("No docked player ship found");
             continue;
         };
@@ -87,11 +88,19 @@ fn handle_undock(
         // Update docked state resource
         docked_state.undock();
 
-        // Transition camera to tactical follow mode (isometric view)
+        // Transition camera to follow mode: a tactical iso view tracking the
+        // ship. Arm a focus goal so the distance eases from the docked framing
+        // to the follow distance instead of hard-snapping. The orbit target is
+        // left to `track_camera_target`, which locks it to the ship.
         camera_state.mode = CameraMode::Follow;
         camera_state.target_entity = Some(player_entity);
-        camera_state.follow_distance = 45.0;  // Higher for tactical view
-        camera_state.follow_height = 35.0;    // Isometric angle
+        camera_state.follow_distance = 45.0; // Higher for tactical view
+        camera_state.follow_height = 35.0; // Isometric angle
+        focus_goal.arm(
+            None,
+            Some(camera_state.follow_distance),
+            Some(crate::camera::tactical_rotation()),
+        );
 
         // UI removed - gameplay only
         // setup_flight_ui(commands.reborrow());
@@ -111,6 +120,7 @@ fn handle_docking(
     mut events: EventReader<DockEvent>,
     mut docked_state: ResMut<DockedState>,
     mut camera_state: ResMut<CameraState>,
+    mut focus_goal: ResMut<OrbitFocusGoal>,
     identifiable_query: Query<&Identifiable>,
     // flight_ui_query removed - UI no longer needed
 ) {
@@ -134,9 +144,15 @@ fn handle_docking(
         // Update docked state resource
         docked_state.dock_at(event.station);
 
-        // Transition camera to cinematic mode
-        camera_state.mode = CameraMode::Cinematic;
+        // Transition camera back to the docked tactical framing (Orbit on the
+        // station), easing the distance in.
+        camera_state.mode = CameraMode::Orbit;
         camera_state.target_entity = Some(event.station);
+        focus_goal.arm(
+            None,
+            Some(crate::camera::DOCKED_FRAMING_DISTANCE),
+            Some(crate::camera::tactical_rotation()),
+        );
 
         // UI removed - no longer needed
         // Despawn flight HUD