Add signal contracts for reachability, exploitability, trust, and unknown symbols

- Introduced `ReachabilityState`, `RuntimeHit`, `ExploitabilitySignal`, `ReachabilitySignal`, `SignalEnvelope`, `SignalType`, `TrustSignal`, and `UnknownSymbolSignal` records to define various signal types and their properties.
- Implemented JSON serialization attributes for proper data interchange.
- Created project files for the new signal contracts library and corresponding test projects.
- Added deterministic test fixtures for micro-interaction testing.
- Included cryptographic keys for secure operations with cosign.

src/Web/StellaOps.Web/angular.json

@@ -13,7 +13,7 @@
       "root": "",
       "sourceRoot": "src",
       "prefix": "app",
-      "architect": {
+      "architect": {
         "build": {
           "builder": "@angular-devkit/build-angular:application",
           "options": {
@@ -100,13 +100,32 @@
                 "output": "."
               }
             ],
-            "styles": [
-              "src/styles.scss"
-            ],
-            "scripts": []
-          }
-        }
-      }
-    }
-  }
-}
+            "styles": [
+              "src/styles.scss"
+            ],
+            "scripts": []
+          }
+        },
+        "storybook": {
+          "builder": "@storybook/angular:start-storybook",
+          "options": {
+            "configDir": ".storybook",
+            "browserTarget": "stellaops-web:build",
+            "port": 4600,
+            "quiet": true,
+            "ci": true
+          }
+        },
+        "build-storybook": {
+          "builder": "@storybook/angular:build-storybook",
+          "options": {
+            "configDir": ".storybook",
+            "browserTarget": "stellaops-web:build",
+            "outputDir": "storybook-static",
+            "quiet": true
+          }
+        }
+      }
+    }
+  }
+}