docs(core): record unlimited stock recycling as an intentional rules decision

Resolves the Draw-1 recycle question from the June 500-game audit:
unlimited recycling with upstream score penalties is deliberate,
matching mainstream digital solitaire rather than strict 3-pass
tournament rules. The difficulty seed catalog and the winnable-deal
solver are verified under this rule, so a hard pass limit must not be
introduced casually.

- ARCHITECTURE.md: new 'Rules decisions' note in the solitaire_core
  section
- GameState::draw() doc comment points at the decision record
- New lock-in test draw_one_recycling_is_unlimited_by_design asserts
  10+ recycles are never rejected

Closes #117

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

ARCHITECTURE.md

@@ -109,6 +109,18 @@ Owns:
 - Achievement unlock condition evaluation
 - Seeded RNG for reproducible deals
 
+**Rules decisions:**
+- **Stock recycling is unlimited in every draw mode — by design.** Extra
+  passes through the stock are discouraged via the upstream score penalty
+  (applied by the `card_game`/`klondike` session), never blocked with a
+  `MoveError`. This matches mainstream digital solitaire (unlimited redeals
+  in Draw-1) rather than strict tournament rules (3-pass cap). It is load-
+  bearing: the difficulty seed catalog and the winnable-deal solver are
+  verified under unlimited recycling, so introducing a hard pass limit would
+  invalidate both. Locked in by the
+  `draw_one_recycling_is_unlimited_by_design` test in
+  `solitaire_core/src/game_state.rs`. (Decision record: Gitea issue #117.)
+
 ### `solitaire_sync`
 **Dependencies:** `serde`, `serde_json`, `uuid`, `chrono` only.
 

CHANGELOG.md

@@ -8,6 +8,12 @@ project follows [Semantic Versioning](https://semver.org/).
 
 ### Added
 
+- **Rules decision record: unlimited stock recycling.** Documented in
+  `ARCHITECTURE.md` that unlimited recycling with score penalties (matching
+  mainstream digital solitaire) is intentional, and locked it in with a core
+  test — the difficulty seed catalog and winnable-deal solver are verified
+  under this rule. Resolves the last open finding from the June 500-game
+  audit (issue #117).
 - **Analytics validation runbook.** Documented native Matomo live validation,
   expected event payloads, and the current web/WASM analytics split.
 - **Android smoke-test runbook.** Updated the Android doc with the current

solitaire_core/src/game_state.rs

@@ -863,6 +863,13 @@ impl GameState {
     }
 
     /// Draw cards from stock to waste. When stock is empty, recycles waste back to stock.
+    ///
+    /// Recycling is deliberately unlimited in every draw mode: extra passes
+    /// are discouraged through the upstream score penalty, never rejected
+    /// with a [`MoveError`]. The difficulty seed catalog and the
+    /// winnable-deal solver are verified under this rule — see the
+    /// "Rules decisions" note in `ARCHITECTURE.md` (`solitaire_core`
+    /// section) before considering a hard pass limit.
     pub fn draw(&mut self) -> Result<(), MoveError> {
         if self.is_won() {
             return Err(MoveError::GameAlreadyWon);
@@ -1222,6 +1229,30 @@ mod tests {
         );
     }
 
+    #[test]
+    fn draw_one_recycling_is_unlimited_by_design() {
+        // Rules decision (Gitea #117): stock recycling is unlimited in every
+        // draw mode. Extra passes are discouraged via the upstream score
+        // penalty, never blocked with a MoveError. The difficulty seed
+        // catalog and the winnable-deal solver are verified under this rule,
+        // so a hard pass limit must not be introduced casually — see the
+        // "Rules decisions" note in ARCHITECTURE.md (`solitaire_core`).
+        let mut game = game_at_first_recycle().expect("could not reach recycle");
+        // ~24 draws per Draw-1 pass; 2_000 draws is ample budget for 10 passes.
+        for _ in 0..2_000 {
+            if game.recycle_count() >= 10 {
+                break;
+            }
+            game.draw()
+                .expect("unlimited recycling: draw must never fail on pass count");
+        }
+        assert!(
+            game.recycle_count() >= 10,
+            "expected at least 10 recycles within the draw budget, got {}",
+            game.recycle_count(),
+        );
+    }
+
     #[test]
     fn undo_applies_minus_15_penalty_via_upstream_score() {
         // A foundation move scores +10 upstream; undoing it nets the move score