minor docs fix

Author: nx10

ARCHITECTURE.md

@@ -42,7 +42,7 @@ flowchart LR
 | ------------- | -------------------------------------------------------------------------------------------------------------------------- |
 | **ir**        | Canonical expression tree (Expr = Literal \| Sequence \| Alternative \| Optional \| Repeat \| Int \| Float \| Str \| Path) |
 | **ir/passes** | Optimization passes: flatten, simplify, canonicalize, remove-empty                                                         |
-| **bindings**  | Solved types (BoundType = scalar \| bool \| count \| literal \| optional \| list \| struct \| union \| nullable)           |
+| **bindings**  | Solved types (BoundType = scalar \| bool \| count \| literal \| optional \| list \| struct \| union)                       |
 | **solver**    | IR → Bindings via pattern matching                                                                                         |
 | **manifest**  | Optional metadata: Project > Package > App                                                                                 |
 | **frontend**  | Parsers producing IR                                                                                                       |
@@ -76,7 +76,7 @@ The IR is the skeleton of the command line; the bindings define the typed interf
 | **IR**              | Dataclass hierarchy (`Param[T]` with body types)                                         | Algebraic expr tree with `kind` discriminant                                             |
 | **Optimization**    | Minimal (string merging)                                                                 | Pass-based pipeline (flatten, simplify, canonicalize)                                    |
 | **Type resolution** | Direct mapping in frontend; each backend re-derives types via language provider protocol | Solver produces a universal `BoundType` tree; backends just translate it                 |
-| **Backends**        | Python mature, TS/R partial; each implements a complex `LanguageProvider` protocol       | All stubs (architecture in place); should be simpler since solver does the heavy lifting |
+| **Backends**        | Python mature, TS/R partial; each implements a complex `LanguageProvider` protocol       | TypeScript + JSON Schema complete; Python/R stubs; simpler since solver does heavy lifting |
 | **Output files**    | First-class: path templates with param refs, suffix stripping, fallbacks                 | Not yet modeled to the same degree                                                       |
 
 Key Styx 1 features to eventually match: