make marble creation a weak claim

src/marble_engine/tile.rs

@@ -485,3 +485,35 @@ impl Comparison {
 		}
 	}
 }
+
+impl Claim {
+	#[must_use]
+	/// returns `was_free`
+	pub fn claim(&mut self) -> bool {
+		let mut was_free = false;
+		*self = match self {
+			Claim::Free => {
+				was_free = true;
+				Claim::Claimed
+			}
+			Claim::ClaimedIndirect | Claim::BlockedIndirect => Claim::Claimed,
+			Claim::Claimed | Claim::Blocked => Claim::Blocked,
+		};
+		was_free
+	}
+
+	#[must_use]
+	/// returns `was_free`
+	pub fn claim_indirect(&mut self) -> bool {
+		let mut was_free = false;
+		*self = match self {
+			Claim::Free => {
+				was_free = true;
+				Claim::ClaimedIndirect
+			}
+			Claim::ClaimedIndirect => Claim::BlockedIndirect,
+			_ => *self,
+		};
+		was_free
+	}
+}