fix(preprod): Align relative_diff extract_value with frontend percentage convention

extract_value returned a ratio (0.05 for 5%) while the frontend stores
percentage-scale values (5.0 for 5%), so the condition check was always
false and relative_diff monitors never triggered. Multiply by 100 to
match the frontend convention and align with VCS status checks.

Refs LINEAR-EME-985
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: mtopo27

src/sentry/preprod/size_analysis/grouptype.py

@@ -193,7 +193,7 @@ def extract_value(self, data_packet: SizeAnalysisDataPacket) -> SizeAnalysisEval
                 return self._extract_head(data_packet) - self._extract_base(data_packet)
             case "relative_diff":
                 base = self._extract_base(data_packet)
-                return (self._extract_head(data_packet) - base) / base
+                return ((self._extract_head(data_packet) - base) / base) * 100
             case _:
                 raise ValueError(f"Unknown threshold_type: {threshold_type}")
 

tests/sentry/preprod/size_analysis/test_grouptype.py

@@ -281,11 +281,11 @@ def test_evaluate_relative_diff(self):
         condition_group = self.create_data_condition_group(
             organization=self.project.organization,
         )
-        # Trigger when relative diff > 0.1 (10%)
+        # Trigger when relative diff > 10 (10%)
         self.create_data_condition(
             condition_group=condition_group,
             type=Condition.GREATER,
-            comparison=0.1,
+            comparison=10,
             condition_result=DetectorPriorityLevel.HIGH,
         )
         detector = self.create_detector(
@@ -296,7 +296,7 @@ def test_evaluate_relative_diff(self):
             workflow_condition_group=condition_group,
         )
 
-        # (5000000 - 4000000) / 4000000 = 0.25 > 0.1
+        # (5000000 - 4000000) / 4000000 = 25% > 10%
         data_packet: SizeAnalysisDataPacket = DataPacket(
             source_id="test",
             packet={
@@ -316,11 +316,11 @@ def test_evaluate_relative_diff_no_trigger_when_below_threshold(self):
         condition_group = self.create_data_condition_group(
             organization=self.project.organization,
         )
-        # Trigger when relative diff > 0.1 (10%)
+        # Trigger when relative diff > 10 (10%)
         self.create_data_condition(
             condition_group=condition_group,
             type=Condition.GREATER,
-            comparison=0.1,
+            comparison=10,
             condition_result=DetectorPriorityLevel.HIGH,
         )
         detector = self.create_detector(
@@ -331,7 +331,7 @@ def test_evaluate_relative_diff_no_trigger_when_below_threshold(self):
             workflow_condition_group=condition_group,
         )
 
-        # (5000000 - 4900000) / 4900000 ≈ 0.02 < 0.1
+        # (5000000 - 4900000) / 4900000 ≈ 2.04% < 10%
         data_packet: SizeAnalysisDataPacket = DataPacket(
             source_id="test",
             packet={