Terminology: BattleTech missions, not races

"Race" is Red Planet's term (it's a racing game) and rode in with the
RPL4LOBBY port. In BattleTech the gameplay unit is a MISSION. Sweep it out
of the front-end / lobby / marshal code + the roadmap and steamification
digest: rename the public API BTLobby_Push/PullRaceResults ->
Push/PullMissionResults, the internal PrimeHostedRace -> PrimeHostedMission,
the deferred marshal InstallNetworkRace -> InstallNetworkMission, and the
user-facing strings ("STEAM MISSION LOBBY", "L A U N C H  M I S S I O N",
"HOST/JOIN STEAM MISSION"). Comments follow. No behavior change; both gates
(default + BT412_STEAM) still build + link clean.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/BT412-ROADMAP.md

@@ -139,7 +139,7 @@ identical-to-baseline → take RP412's file verbatim, diverged → hand-apply th
   console on its own thread over NetTransport — egg chunks + ACK, RunMission ×2
   (mirror btconsole.py), stays connected (fixes the console-loss listener bug for
   solo), owns the mission clock, StopMission at `length=` expiry, launcher-role loop,
-  `InstallNetworkRace` marshal for remote pods.
+  `InstallNetworkMission` marshal for remote pods.
 - **5c Score intake — genuinely new for BT** (no mission-end flow exists): a
   `gConsoleScoreSink` equivalent through `BTPlayer`; v1 results screen = kills/deaths
   per pilot from the Comm-MFD `pilotList` tally at stop.
@@ -160,7 +160,7 @@ identical-to-baseline → take RP412's file verbatim, diverged → hand-apply th
 > `Application::StopMissionMessage` at the chosen length; it snapshots per-pilot
 > kills/deaths at the stop (BT's own score model — msgID 0x18 stays a stub). The
 > single-binary loop is a RELAUNCH per mission (`CreateProcessW`; avoids the stale
-> `gBT*`-global re-init crash), showing a GDI "MISSION COMPLETE" scoreboard between races.
+> `gBT*`-global re-init crash), showing a GDI "MISSION COMPLETE" scoreboard between missions.
 > WinMain (`game/btl4main.cpp`) wires front-end-mode detection, the marshal arm, the
 > results screen + relaunch, and the launch-mode branch (solo/host/member). Details in
 > `context/steamification.md`.
@@ -170,7 +170,7 @@ identical-to-baseline → take RP412's file verbatim, diverged → hand-apply th
 - **`game/reconstructed/btl4lobby.cpp`** (skeleton: `RPL4LOBBY.cpp` — mechanics
   generic): lobby owner = console; member data = FakeIP + fake console/game ports +
   persona + loadout (**mech**/color/badge); nonced launch roster → `RegisterPeer` all →
-  owner hosts via egg+marshal, members join as network pods; Push/PullRaceResults
+  owner hosts via egg+marshal, members join as network pods; Push/PullMissionResults
   distribute the score sheet. FE gains HOST/JOIN screens.
 - Author `docs/STEAM-3-MACHINE-TEST.md` for BT (adapt RP412's; keep its gotchas:
   disable Steam Input on 480, one Steam account per machine, abort key).
@@ -183,14 +183,14 @@ identical-to-baseline → take RP412's file verbatim, diverged → hand-apply th
 > `BT412_STEAM`, full ISteamMatchmaking room under it). Built: the room screen (green-on-black,
 > like the menu), member data exchange (FakeIP + fake console/game ports + persona +
 > mech/color/badge), the nonced "go" launch roster → `SteamNetTransport_RegisterPeer` all peers,
-> and Push/PullRaceResults over lobby data. The menu shows HOST/JOIN when `BTLobby_Available()`
+> and Push/PullMissionResults over lobby data. The menu shows HOST/JOIN when `BTLobby_Available()`
 > (Steam transport up); a launch routes through `BTFrontEnd_LastLaunchMode()`: **host** builds the
 > egg with every member as a `[pilots]` entry + owns the marshal clock, **member** enters as a
 > network pod on `:1501` (`SetNetworkCommonFlatAddress` + `gConsoleLossEndsMission`). WinMain
 > installs the Steam transport on `BT412STEAM` env. **Remaining / deferred:** the host→member
-> **wire egg-feed marshal** (`InstallNetworkRace` — the owner streaming eggs to remote pods) is
+> **wire egg-feed marshal** (`InstallNetworkMission` — the owner streaming eggs to remote pods) is
 > NOT built; a member currently waits for a console connection that only that marshal provides, so
-> a live host+member race needs it. The lobby OBJECT does not survive the per-mission relaunch
+> a live host+member mission needs it. The lobby OBJECT does not survive the per-mission relaunch
 > (documented single-binary limitation — everyone lands on a fresh menu, not back in the room).
 > `docs/STEAM-3-MACHINE-TEST.md` for BT is not yet authored. Details in `context/steamification.md`.