Remove executor, add buy/sell to Alpaca, move capital allocation to Bot

Replace the Executor logging placeholder with real buy/sell methods on
the Alpaca class that place market orders via createOrder and return the
fill price. Strategies now receive their capital amount directly and
place orders themselves. Bot accepts StrategyAllocation[] to decouple
capital allocation from strategy definition.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/bot.ts

@@ -1,23 +1,25 @@
 import { Alpaca } from "./alpaca";
 import { Strategy } from "./strategy";
-import { Executor } from "./executor";
 import { isMarketOpen, waitForNextOpen } from "./trading";
 
+export interface StrategyAllocation {
+    strategy: Strategy;
+    capitalAllocation: number;
+}
+
 export class Bot {
     private alpaca: Alpaca;
-    private strategies: Strategy[];
-    private executor: Executor;
+    private allocations: StrategyAllocation[];
 
-    constructor(alpaca: Alpaca, strategies: Strategy[]) {
-        const totalAllocation = strategies.reduce((sum, s) => sum + s.capitalAllocation, 0);
+    constructor(alpaca: Alpaca, allocations: StrategyAllocation[]) {
+        const totalAllocation = allocations.reduce((sum, a) => sum + a.capitalAllocation, 0);
         if (totalAllocation > 1.0) {
             throw new Error(
                 `Capital allocations sum to ${totalAllocation}, which exceeds 1.0`
             );
         }
         this.alpaca = alpaca;
-        this.strategies = strategies;
-        this.executor = new Executor(alpaca);
+        this.allocations = allocations;
     }
 
     async runDay(): Promise<void> {
@@ -26,14 +28,13 @@ export class Bot {
             console.log('waiting for open');
             await waitForNextOpen(this.alpaca);
         }
-	    const account = await this.alpaca.getAccount();
-	    const totalCapital = parseFloat(account.cash);
-	
-        await Promise.all(
-            this.strategies.map(async (strategy) => {
-                const signals = await strategy.execute(this.alpaca);
+        const account = await this.alpaca.getAccount();
+        const totalCapital = parseFloat(account.cash);
 
-                await this.executor.executeSignals(strategy, signals, totalCapital);
+        await Promise.all(
+            this.allocations.map(async ({ strategy, capitalAllocation }) => {
+                const capitalAmount = totalCapital * capitalAllocation;
+                await strategy.execute(this.alpaca, capitalAmount);
             })
         );
     }