All prototype targets now share `PrototypeTargetRegistry.SharedLockRadius`
(= 6 m). Anchors moved to alpha `(-3, 0.5, -3)` and beta `(3, 0, 3)` so
the two 6 m rings overlap ~3.5 m wide centered at origin, letting Tab
flip between targets without locomotion. Spawn `(-5, -5)` keeps alpha
in range (~2.83 m) and beta out (~11.31 m) so the existing soft-lock
denial QA path at spawn still holds.
`prototype_target_constants.gd` mirrors the shared radius + new anchors.
The range-aware Tab picker now **skips the currently-locked id** so Tab
always expresses a swap intent — if the only in-range target is already
locked, the fallback picks the next cycle id and the server denies
(preserves NEO-23's "Tab = visible denial when no swap possible" rule).
Tests:
- Server: new `PlayerTargetStateReaderTests.ComputeValidity_AtOrigin_…`
asserts both targets report `Ok` at origin. Existing boundary test
rewritten for the new alpha anchor.
- Client: new `test_tab_from_locked_alpha_at_origin_swaps_to_beta_when_both_in_range`
and `test_tab_when_only_current_lock_is_in_range_falls_back_to_cycle_for_denial`.
Existing in-range/out-of-range positions updated for the new layout.
Server 59/59 and client 95/95 suites pass.
Plan Decision 7, review follow-up #4, manual QA section 5 (new "Tab-flip
at origin" overlap sanity), and README updated. Per-target radii will
return with real combat design (E5.M1) — this is a prototype stub.
VinPropane