Update RSPEC

rules/S7463/metadata.json

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+{
+}

rules/S7463/rust/metadata.json

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+{
+  "title": "`saturating_sub` should be used to avoid subtraction underflow",
+  "type": "BUG",
+  "status": "ready",
+  "remediation": {
+    "func": "Constant\/Issue",
+    "constantCost": "5min"
+  },
+  "tags": [
+    "clippy"
+  ],
+  "defaultSeverity": "Major",
+  "ruleSpecification": "RSPEC-7463",
+  "sqKey": "S7463",
+  "scope": "All",
+  "defaultQualityProfiles": ["Sonar way"],
+  "quickfix": "unknown",
+  "code": {
+    "impacts": {
+      "RELIABILITY": "MEDIUM"
+    },
+    "attribute": "LOGICAL"
+  }
+}

rules/S7463/rust/rule.adoc

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+== Why is this an issue?
+
+Using conditional subtraction ``++if a > b { b - a } else { 0 }++`` can lead to an unintended underflow, which can cause bugs or unexpected behaviors. The ``++saturating_sub++`` method ensures that the subtraction does not underflow by returning zero if the result would have been negative.
+
+=== Code examples
+
+==== Noncompliant code example
+
+[source,rust,diff-id=1,diff-type=noncompliant]
+----
+let a = 12u32;
+let b = 13u32;
+let result = if a > b { b - a } else { 0 }; // Noncompliant: Potential underflow condition.
+----
+
+==== Compliant solution
+
+[source,rust,diff-id=1,diff-type=compliant]
+----
+let a = 12u32;
+let b = 13u32;
+let result = a.saturating_sub(b); // Compliant: Safe subtraction using saturating_sub.
+----
+
+== Resources
+=== Documentation
+
+* Clippy Lints - https://rust-lang.github.io/rust-clippy/master/index.html#inverted_saturating_sub