fix tracks to all be EW. no more NS tracks

docs/rules/implications.md

@@ -46,7 +46,7 @@ All nine answers are implemented, **170 tests passing**:
 | Q4 Lockouts | `isLockedOut()` rejects the placement with `FACILITY_LOCKED`. |
 | Q5 Run-around | Nothing to do — reachability is geometric, so a built bypass already works. |
 | Q6 Space-use | **Solitaire decks omit all 22 opponent-directed cards**: `buildDeck('solitaire')` returns **93**, competitive returns 115. |
-| Q7 Downward-only | Office cards have a stub **below only**; turnout and curve legs always diverge south; placement and modifier candidates above the Running Track are rejected. §9's "nine nearby spots" is really **six**. |
+| Q7 45° geometry | The through track runs east-west across the **middle** of every card; there is no north-south track. Every leg leaves at **45° through the middle of the north or south edge**, so two stacked cards join only when their legs share a diagonal (`joins`/`slopeAt` in `track.ts`). Handedness is that diagonal, and a card turns 180° but never flips, so each has **two** orientations. Office and industry cards carry a plain through track and no stub. A district grows on **both** sides of the Running Track, so §9's "nine nearby spots" really is nine. |
 | Q8 Crew Tray cap | Already correct. |
 | Q9 Second Section | `newTrain.secondSection` plays on a train due out; an identical train is made up behind it next New Train Phase. The **Sister trains optional rule is removed** from Appendix B. |
 
@@ -610,7 +610,7 @@ anything), **Space-use** (lowest mechanical weight).
 | 5 Extra/Timetabled ties | **moot** | Extras are X13–X22; the tie cannot occur |
 | 6 Victory conditions | **needs re-derivation** | new revenue sources and point losses |
 | 7 Terminology | **stands** | |
-| 8 Office junction stubs | **needs checking against the art** | `tracks.png` shows the through-line at the card's top edge, not the middle |
+| 8 Office junction stubs | **superseded** | `tracks.png` gives every office and industry card a plain east-west track and no stub; a district hangs off a turnout |
 | 9 Make-up round repeats | **stands** | |
 | 10 Card faces | **superseded** | this is the real card list |
 | 11 Track orientation | **superseded** | handedness is printed; both hands are supplied |
@@ -656,7 +656,7 @@ Recorded as they are given, so nothing is lost between sessions.
 | 4 | What does a lockout prevent? | **Building both in your district.** If you hold a Mine Tipple, a Power Plant card is unplayable in your Office Area, and vice versa. Each locked pair is a producer and the consumer of the same commodity, so this forces traffic to flow *between* districts — a deliberate multiplayer-interdependence mechanic. In solitaire it simply narrows the build options. |
 | 5 | Is a run-around a card? | **No — a pattern built from the track supply.** Opposite-hand turnouts joined by straights. Nothing to implement: reachability is computed from geometry, so a valid bypass already works. This explains the 8 turnouts per player, and makes §A.5's facing-point move a building achievement rather than a lucky draw. |
 | 6 | How are Space-use cards played? | **At another player's district**, consuming a grid cell they wanted. This explains Water Column ("remove any Watertower in *your* district" — one an opponent gave you) and Vandalism (exploits a Hobo Jungle you were saddled with). A second, milder attack channel alongside the Action cards. **In solitaire they have no target** — see the note below. |
-| 7 | Does a district grow both ways? | **Downward only** — the through-track sits at the card's top edge and everything diverges beneath it, matching `tracks.png`. A district is a Running Track with all Secondary Track hanging below. **Supersedes Gap 8's north-and-south stubs.** Consequences: buildable area halves; districts become long and shallow; §9's nine-spot Modifier neighbourhood needs rewording, since three of the nine spots are above the track and no longer exist. |
+| 7 | Does a district grow both ways? | **Yes, both** — measured off `tracks.png` rather than inferred. The through track runs east-west across the exact vertical middle of every card, and every diverging leg leaves at 45° through the middle of the north or south edge. Turning a card 180° swaps that leg between north and south, so a turnout serves either side. **Supersedes Gap 8's stubs in the other direction**: no office or industry card carries a leg at all, so a district hangs off a turnout laid on the Running Track. Consequences: no card joins north to south, so descending a row costs at least two cards (leg out, then a curve turning the run back east-west) and districts are wide and shallow; and a printed card's handedness fixes which diagonal its leg lies on, so a run-around needs one card of each hand. |
 | 8 | Any cap on trains in play? | **No — Crew Trays are the only limit.** All 12 timetabled trains may end up scheduled; Extras run on top ad hoc; a due train with no free crew is held (§7). Already implemented. This makes the Crew Tray count (`players + 3`) the single most important balance dial, and "held" a common visible state. |
 | 9 | What is the Second Section card? | **A card played on a train that is due out.** A second identical train runs immediately behind it — same number, rules and consist — and needs its own Crew Tray. It deliberately creates the following-train situation §8.1 makes the Superintendent rule on, so a player can force the game's central decision onto the table. Explains the green flags on the artwork. **Supersedes the "Sister trains" optional rule**, which should be removed from Appendix B. |
 
@@ -700,8 +700,9 @@ once the speed model is implemented; the Crew Tray count is the obvious dial.
 5. **Run-around** — we treat it as a card; it is not in the supply. Is it a pattern built from two
    turnouts?
 6. **Space-use cards** — played at yourself as a cost of drawing, or at opponents?
-7. **Where the Office's junction stubs are.** `tracks.png` draws the through-line along the top edge
-   with curves diverging downward. Gap 8 assumed stubs above *and* below a centred track.
+7. ~~**Where the Office's junction stubs are.**~~ **Settled by measuring `tracks.png`**: the through
+   line is dead centre on every card, not along the top edge, and no office or industry card has a
+   stub in either direction. See Q7 above.
 8. **Are all 22 trains in play at once**, or is the timetable still 12 slots with Extras run on top?
 9. **Second Section** — is it a card played on a scheduled train, or its own train?