Initial package implementation: operations registry, call protocol, and adapters

Extracted from alkhub_ts packages/core/operations/ and packages/core/mcp/.
- Runtime-agnostic (injected fs/env deps, no Deno globals)
- Direct @logtape/logtape import instead of logger wrapper
- PendingRequestMap with pubsub-wired call protocol
- Peer-dep isolation for MCP adapter (sub-path export)
- Schema const naming convention (XSchema + X type alias)
- 68 tests passing, build + lint + test all green

src/index.ts

@@ -0,0 +1,18 @@
+export { OperationType, OperationContextSchema, OperationDefinitionSchema, OperationSpecSchema, AccessControlSchema, ErrorDefinitionSchema } from "./types.js";
+export type { IOperationDefinition, OperationHandler, SubscriptionHandler, Identity, OperationEnv, OperationContext, OperationSpec, AccessControl, ErrorDefinition } from "./types.js";
+export { OperationRegistry } from "./registry.js";
+export { formatValueErrors, assertIsSchema, validateOrThrow, collectErrors } from "./validation.js";
+export { buildEnv } from "./env.js";
+export type { PendingRequestMap, EnvOptions } from "./env.js";
+export { FromSchema } from "./from_schema.js";
+export { FromOpenAPI, FromOpenAPIFile, FromOpenAPIUrl } from "./from_openapi.js";
+export type { OpenAPISpec, OpenAPIOperation, OpenAPIParameter, HTTPServiceConfig, OpenAPIFS } from "./from_openapi.js";
+export { scanOperations } from "./scanner.js";
+export type { OperationManifest, ScannerFS } from "./scanner.js";
+export { CallError, InfrastructureErrorCode, mapError } from "./error.js";
+export type { CallErrorCode } from "./error.js";
+export { PendingRequestMap as PendingRequestMapClass, buildCallHandler } from "./call.js";
+export type { CallEventMap, CallEventMapValue, CallRequestedEvent, CallRespondedEvent, CallAbortedEvent, CallErrorEvent, CallHandler, CallHandlerConfig } from "./call.js";
+export { subscribe } from "./subscribe.js";
+export { createMCPClient, closeMCPClient, MCPClientLoader } from "./from_mcp.js";
+export type { MCPClientConfig, MCPClientWrapper } from "./from_mcp.js";