feat: Implement Filesystem and MongoDB provenance writers for PackRun execution context

- Added `FilesystemPackRunProvenanceWriter` to write provenance manifests to the filesystem.
- Introduced `MongoPackRunArtifactReader` to read artifacts from MongoDB.
- Created `MongoPackRunProvenanceWriter` to store provenance manifests in MongoDB.
- Developed unit tests for filesystem and MongoDB provenance writers.
- Established `ITimelineEventStore` and `ITimelineIngestionService` interfaces for timeline event handling.
- Implemented `TimelineIngestionService` to validate and persist timeline events with hashing.
- Created PostgreSQL schema and migration scripts for timeline indexing.
- Added dependency injection support for timeline indexer services.
- Developed tests for timeline ingestion and schema validation.

bench/reachability-benchmark/cases/java/spring-guarded/src/AppTest.java

@@ -0,0 +1,29 @@
+package bench.reachability;
+
+import java.io.*;
+import java.util.*;
+import java.util.Base64;
+
+public class AppTest {
+    private static String serialize(Object obj) throws IOException {
+        ByteArrayOutputStream bos = new ByteArrayOutputStream();
+        ObjectOutputStream oos = new ObjectOutputStream(bos);
+        oos.writeObject(obj);
+        oos.close();
+        return Base64.getEncoder().encodeToString(bos.toByteArray());
+    }
+
+    public static void main(String[] args) throws Exception {
+        String payload = serialize("hi");
+        Map<String, String> body = Map.of("payload", payload);
+        Map<String, String> env = Map.of("ALLOW_DESER", "false");
+        var res = App.handleRequest(body, env);
+        assert res.status() == 403 : "status";
+        assert res.body().equals("forbidden") : "body";
+        File outDir = new File("outputs");
+        outDir.mkdirs();
+        try (FileWriter fw = new FileWriter(new File(outDir, "SINK_BLOCKED"))) {
+            fw.write("true");
+        }
+    }
+}