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-lock.json

@@ -21,7 +21,12 @@
         "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"
       }
     },
     "node_modules/@anthropic-ai/claude-agent-sdk": {
@@ -253,6 +258,23 @@
         "url": "https://opencollective.com/libvips"
       }
     },
+    "node_modules/@types/js-yaml": {
+      "version": "4.0.9",
+      "resolved": "https://registry.npmjs.org/@types/js-yaml/-/js-yaml-4.0.9.tgz",
+      "integrity": "sha512-k4MGaQl5TGo/iipqb2UDG2UwjXziSWkh0uysQelTlJpX1qGlpUZYm8PnO4DxG1qBomtJUdYJ6qR6xdIah10JLg==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@types/node": {
+      "version": "25.0.3",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-25.0.3.tgz",
+      "integrity": "sha512-W609buLVRVmeW693xKfzHeIV6nJGGz98uCPfeXI1ELMLXVeKYZ9m15fAMSaUPBHYLGFsVRcMmSCksQOrZV9BYA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "undici-types": "~7.16.0"
+      }
+    },
     "node_modules/@types/tinycolor2": {
       "version": "1.4.6",
       "resolved": "https://registry.npmjs.org/@types/tinycolor2/-/tinycolor2-1.4.6.tgz",
@@ -615,6 +637,27 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/typescript": {
+      "version": "5.9.3",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.9.3.tgz",
+      "integrity": "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "bin": {
+        "tsc": "bin/tsc",
+        "tsserver": "bin/tsserver"
+      },
+      "engines": {
+        "node": ">=14.17"
+      }
+    },
+    "node_modules/undici-types": {
+      "version": "7.16.0",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-7.16.0.tgz",
+      "integrity": "sha512-Zz+aZWSj8LE6zoxD+xrjh4VfkIG8Ya6LvYkZqtUQGJPZjYl53ypCaUwWqo7eI0x66KBGeRo+mlBEkMSeSZ38Nw==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/widest-line": {
       "version": "5.0.0",
       "resolved": "https://registry.npmjs.org/widest-line/-/widest-line-5.0.0.tgz",