Tighten multiplayer transport callback ownership

docs/atlas/route-entry-and-trackers.md

@@ -65,6 +65,13 @@ Current bounded time-side cutover:
   delegates through `0x0046a4b0`
 - the recovered `>= 0x67`, `>= 0x68`, `>= 0x69`, and `>= 0x6a` caller pattern now lines up with
   executable build values `1.03`, `1.04`, `1.05`, and `1.06`
+- that makes the tracker cutover read more cleanly too:
+  `0x004a65b0` is now best treated as a pre-`1.03` versus `1.03+` route-metric compatibility
+  dispatcher, not as any gameplay-time or era-side mode switch
+- the branch source is session-aware too:
+  when multiplayer state is active, the same cutover can follow the session-side build path rather
+  than only the local executable version, so mixed-version compatibility is now the strongest
+  current explanation for why this lower metric split exists at all
 - nearby callers now make two more compatibility reads concrete:
   build `1.04+` keeps one `Recycling Plant` stem-specific branch alive inside `0x004101e0`, and
   build `1.05+` skips one older descriptor-side attenuation fallback in that same rebuild family
@@ -120,6 +127,8 @@ What this note is for:
 
 Highest-value open edge:
 
-- The remaining semantic edge is why build `1.03+` selects the weighted tracker branch in
-  `0x004a65b0`, now that the version gate itself is grounded and the linked-transit peer-cache side
-  is tighter as step count plus normalized continuity share rather than a generic ratio.
+- The remaining semantic edge here is narrower now:
+  whether the pre-`1.03` versus `1.03+` tracker metric split has any meaningful downstream effect
+  beyond ranked linked-transit site choice and seeded peer-route choice, since current evidence
+  says the company train-pressure target still sums raw site cache `+0x12` rather than the
+  weighted lanes fed by step count and continuity.