updated documentation to have mermaid diagrams; updated AGENTS.md to note that all future diagrams should be mermaid diagrams first with text-based diagrams as fallback where not applicable

resources/ai/research/data-streaming/README.md

@@ -70,6 +70,16 @@ directly from the buffer each frame without allocations.
 
 ## Immediate Next Steps (when you're ready to implement)
 
+```mermaid
+flowchart TD
+    A["Prototype schema<br/>catalog.fbs: Catalog · CatalogObject · ServerMessage union"]
+    B["Generate Rust code<br/>flatc --rust → api/build.rs · serve WS via axum"]
+    C["Prototype the Odin reader<br/>flatcc FFI · pure-Odin · OdinArrow"]
+    D["Static fixture files<br/>flatc --binary → committed .bin"]
+    E["Cross-language tests<br/>Rust + Odin read the same fixtures identically"]
+    A --> B --> C --> D --> E
+```
+
 1. **Prototype schema first.** Write `catalog.fbs` covering `Catalog`, `CatalogObject`,
    and a `ServerMessage` union (handshake / catalog list / chunk of objects / end).
 2. **Generate Rust code** via `flatc --rust` in an `api/build.rs` (see