feat: reorganize examples and add signature support to JobBuilder

- Reorganized examples into osiris/, sal/, and utils/ folders
- Moved hardcoded scripts to separate .rhai files
- Added signature() method to JobBuilder for job signing
- Updated OSIRIS context to use block_in_place instead of runtime
- Removed runtime field from OsirisContext
- Added typed save() methods for Note and Event objects
- Updated all examples to use new structure and APIs

src/sync_runner.rs

@@ -46,6 +46,24 @@ impl SyncRunner {
         db_config.insert("DB_PATH".into(), db_path.to_string().into());
         db_config.insert("CALLER_ID".into(), job.caller_id.clone().into());
         db_config.insert("CONTEXT_ID".into(), job.context_id.clone().into());
+        
+        // Extract signatories from job signatures, or fall back to env_vars
+        let signatories: Vec<Dynamic> = if !job.signatures.is_empty() {
+            // Use signatures from the job
+            job.signatures.iter()
+                .map(|sig| Dynamic::from(sig.public_key.clone()))
+                .collect()
+        } else if let Some(sig_json) = job.env_vars.get("SIGNATORIES") {
+            // Fall back to SIGNATORIES from env_vars (for backward compatibility)
+            match serde_json::from_str::<Vec<String>>(sig_json) {
+                Ok(sigs) => sigs.into_iter().map(Dynamic::from).collect(),
+                Err(_) => Vec::new(),
+            }
+        } else {
+            Vec::new()
+        };
+        db_config.insert("SIGNATORIES".into(), Dynamic::from(signatories));
+        
         engine.set_default_tag(Dynamic::from(db_config));
         
         debug!("Sync Runner for Context ID '{}': Evaluating script with Rhai engine (job context set).", job.context_id);