Fix/npm-pkg-shared-backend (#1598)

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<!-- This is an auto-generated description by cubic. -->
---
## Summary by cubic
Prepares `@hexclave/shared-backend` for npm publishing with a proper
build, dual ESM/CJS exports, and bundled types. Also simplifies an
import parsing helper for safer matching.

- New Features
- Configure build with `tsdown`; output CJS/ESM and `.d.ts` to `dist/`
and `dist/esm/`.
- Add export map for `.` and `./config-agent` with `require` and
`default` entries plus types.
- Update publish settings: set `main`/`types` to built files, include
only `dist`, exclude tests, and add `build`, `dev`, `clean` scripts.
  - Add repository field and `tsdown.config.ts`.

- Bug Fixes
- Simplified import specifier parsing in `src/index.ts` to push matches
directly and remove unnecessary error throwing.

<sup>Written for commit 9f18bc019a.
Summary will update on new commits.</sup>

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packages/shared-backend/package.json

@@ -1,19 +1,39 @@
 {
   "name": "@hexclave/shared-backend",
   "version": "1.0.17",
-  "private": true,
-  "type": "module",
-  "main": "./src/index.ts",
-  "types": "./src/index.ts",
+  "repository": "https://github.com/hexclave/hexclave",
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
   "exports": {
-    ".": "./src/index.ts",
-    "./config-agent": "./src/config-agent.ts"
+    ".": {
+      "types": "./dist/index.d.ts",
+      "require": {
+        "default": "./dist/index.js"
+      },
+      "default": "./dist/esm/index.js"
+    },
+    "./config-agent": {
+      "types": "./dist/config-agent.d.ts",
+      "require": {
+        "default": "./dist/config-agent.js"
+      },
+      "default": "./dist/esm/config-agent.js"
+    }
   },
   "scripts": {
+    "build": "rimraf dist && tsdown",
+    "clean": "rimraf dist && rimraf node_modules",
+    "dev": "tsdown --watch",
     "lint": "eslint --ext .tsx,.ts .",
     "typecheck": "tsc --noEmit",
     "test": "vitest run"
   },
+  "files": [
+    "dist",
+    "!dist/**/*.test.*",
+    "CHANGELOG.md",
+    "LICENSE"
+  ],
   "dependencies": {
     "@anthropic-ai/claude-agent-sdk": "^0.2.73",
     "@hexclave/shared": "workspace:*",

packages/shared-backend/src/index.ts

@@ -330,11 +330,7 @@ function getRelativeImportSpecifiers(content: string): string[] {
   const importPattern = /\bimport\b(?:[^'"]*?\bfrom\s*)?["'](\.{1,2}\/[^"']+)["']/g;
   let match: RegExpExecArray | null;
   while ((match = importPattern.exec(content)) !== null) {
-    const specifier = match[1];
-    if (specifier == null) {
-      throw new Error("Import specifier regex matched without a capture group.");
-    }
-    specifiers.push(specifier);
+    specifiers.push(match[1]);
   }
   return specifiers;
 }

packages/shared-backend/tsdown.config.ts

@@ -0,0 +1,3 @@
+import createJsLibraryTsupConfig from '../../configs/tsdown/js-library.ts';
+
+export default createJsLibraryTsupConfig({});