v0.8.5 — housekeeping from the audit, and the playtest line retired

The third release from the audit; nothing a player sees changes. CHANGELOG has the detail.

The 0.4.9 playtest line is no longer maintained (Jesse, 2026-09-29): the deploy rule that
existed for it is gone and #85 is moot. The table test (#39 #35 #42a #40) is closed — every
line of the checklist was met at a table. #46 is done and cannot regrow: the 36 unused
declarations are removed and `noUnusedLocals`/`noUnusedParameters` are on; two of them were
dead bot functions from rejected candidates the round said it had deleted. The documents no
longer teach `trainCapSlack` (a knob that throws), point at `as-built.md` (deleted in 0.8.2),
model `officeType` (the engine says `tier`) or describe `collisionOccurred` (never emitted);
the README's account of bot flags now matches the bot's. Five playtest saves committed in
`docs/` against the repository's own rule are in the ignored `playtests/`.

What the audit found and did not fix is written down as TODO #112-#117, each with its reason.
#112 is `docs/plans/structure.md`, the proposal for `http.ts`, `main.ts` and `check`. #117 —
`/api/save` hands a seat the seed mid-game — waits on a conversation.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FrCWubm9GAftYCm2hWdKwK

docs/architecture/protocol.md

@@ -96,7 +96,8 @@ or a replay viewer has to reconstruct the whole board to draw one frame.
 
 Two consequences worth knowing before adding an event:
 
-- **`collisionOccurred` carries `faultPlayer` explicitly** rather than leaving clients to derive it.
+- **`trainsDestroyed` carries the player at fault (`player`) explicitly** rather than leaving clients to
+  derive it (the event was called `collisionOccurred` in this design; the engine emits `trainsDestroyed`).
   Fault depends on *where* the wreck happened — Superintendent for a Mainline card, the local player
   between their Limits (§10) — and getting it wrong misattributes a −5 and, in Competitive, feeds a
   floor that ends the game.