[AI Improvement] [Task] Remove obsolete and unused @types packages from package.json devDependencies

[joehan]

Resolves Buganizer b/563477508

Proposed Improvement

Removed obsolete and unused @types/* packages from package.json devDependencies:

• @types/html-escaper (html-escaper is not installed or used anywhere in src/ or scripts/).
• @types/inquirer and @types/inquirer-autocomplete-prompt (the CLI previously migrated to @inquirer/prompts in src/prompt.ts, which includes its own built-in type declarations; neither legacy inquirer nor inquirer-autocomplete-prompt are installed dependencies).
• @types/multer (multer is not installed or used anywhere).

Also updated npm-shrinkwrap.json via npm install --package-lock-only, which cleanly pruned the four type packages and their unreferenced transitive dependency @types/through.

Verification

• npm run build: TypeScript and MCP app compilation succeeded cleanly.
• npm run test:compile: Type checking passed with 0 errors.
• npm run lint:quiet: ESLint and Prettier passed cleanly.
• mocha src/prompt.spec.ts: All 18 prompt unit tests passed without missing types.

[gemini-code-assist]

Code Review

This pull request removes several unused or redundant TypeScript type definition dependencies from package.json, including @types/html-escaper, @types/inquirer, @types/inquirer-autocomplete-prompt, and @types/multer. No review comments were provided, and there is no additional feedback to address.