feat: audit log of admin writes, sign-ins and key creation, with an audit tab [CI]

backend/src/MoShiro.Backend.Storage.Sqlite/Schema.cs

@@ -191,6 +191,21 @@ internal static class Schema
             connection.Exec("ALTER TABLE join_tokens ADD COLUMN created_by TEXT");
             connection.Exec("ALTER TABLE agents ADD COLUMN added_by TEXT");
             connection.Exec("ALTER TABLE probes ADD COLUMN added_by TEXT");
+            connection.Exec("""
+                CREATE TABLE audit_log (
+                  id INTEGER PRIMARY KEY,
+                  at INTEGER NOT NULL,
+                  user_id TEXT,
+                  actor TEXT NOT NULL,
+                  method TEXT NOT NULL,
+                  action TEXT NOT NULL,
+                  target TEXT,
+                  detail TEXT,
+                  remote TEXT,
+                  success INTEGER NOT NULL
+                )
+                """);
+            connection.Exec("CREATE INDEX ix_audit_time ON audit_log (at)");
             connection.Exec("PRAGMA user_version = 13");
             transaction.Commit();
         }