feat(M3-008): define model capability matrix (#303)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

packages/types/src/provider/index.ts

@@ -1,3 +1,22 @@
+/** Per-model capability metadata used by the routing engine */
+export interface ModelCapability {
+  id: string;
+  provider: string;
+  displayName: string;
+  tier: 'cheap' | 'standard' | 'premium' | 'local';
+  contextWindow: number;
+  maxOutputTokens: number;
+  capabilities: {
+    tools: boolean;
+    vision: boolean;
+    streaming: boolean;
+    reasoning: boolean;
+    embedding: boolean;
+  };
+  costPer1kInput?: number;
+  costPer1kOutput?: number;
+}
+
 /** Known built-in LLM provider identifiers */
 export type KnownProvider =
   | 'anthropic'