feat: typescript migration (#40)

* chore: initialize TypeScript configuration and build setup

- Add tsconfig.json for root and mcp-server with strict type checking
- Install typescript and @types/node as devDependencies
- Add npm build script for TypeScript compilation
- Update main entrypoint to compiled dist/shannon.js
- Update Dockerfile to build TypeScript before running
- Configure output directory and module resolution for Node.js

* refactor: migrate codebase from JavaScript to TypeScript

- Convert all 37 JavaScript files to TypeScript (.js -> .ts)
- Add type definitions in src/types/ for agents, config, errors, session
- Update mcp-server with proper TypeScript types
- Move entry point from shannon.mjs to src/shannon.ts
- Update tsconfig.json with rootDir: "./src" for cleaner dist output
- Update Dockerfile to build TypeScript before runtime
- Update package.json paths to use compiled dist/shannon.js

No runtime behavior changes - pure type safety migration.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

* docs: update CLI references from ./shannon.mjs to shannon

- Update help text in src/cli/ui.ts
- Update usage examples in src/cli/command-handler.ts
- Update setup message in src/shannon.ts
- Update CLAUDE.md documentation with TypeScript file structure
- Replace all ./shannon.mjs references with shannon command

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

* chore: remove unnecessary eslint-disable comments

ESLint is not configured in this project, making these comments redundant.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

---------

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

package.json

@@ -2,9 +2,10 @@
   "name": "shannon",
   "version": "1.0.0",
   "type": "module",
-  "main": "shannon.mjs",
+  "main": "./dist/shannon.js",
   "scripts": {
-    "start": "./shannon.mjs"
+    "build": "tsc",
+    "start": "node ./dist/shannon.js"
   },
   "dependencies": {
     "@anthropic-ai/claude-agent-sdk": "^0.1.0",
@@ -20,6 +21,11 @@
     "zx": "^8.0.0"
   },
   "bin": {
-    "shannon": "./shannon.mjs"
+    "shannon": "./dist/shannon.js"
+  },
+  "devDependencies": {
+    "@types/js-yaml": "^4.0.9",
+    "@types/node": "^25.0.3",
+    "typescript": "^5.9.3"
   }
 }