chore: add ESLint + Prettier, GitHub templates, Playwright install docs

- Add ESLint (typescript-eslint + prettier) and Prettier configuration
- Fix all 22 lint errors: unused imports, dead code, missing error causes
- Add lint/format/format:check scripts to package.json
- Add lint step to CI workflow
- Add GitHub Issue templates (bug report, feature request) and PR template
- Add Playwright install step to README Quick Start and CONTRIBUTING.md
- Update CONTRIBUTING.md with lint/format workflow

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: M00N7682

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,38 @@
+---
+name: Bug Report
+about: Report a bug to help improve imugi
+title: ''
+labels: bug
+assignees: ''
+---
+
+## Description
+
+A clear description of the bug.
+
+## Steps to Reproduce
+
+1.
+2.
+3.
+
+## Expected Behavior
+
+What you expected to happen.
+
+## Actual Behavior
+
+What actually happened.
+
+## Environment
+
+- **OS**: (e.g., macOS 14.2, Ubuntu 22.04)
+- **Node.js**: (e.g., 20.11.0)
+- **imugi version**: (e.g., 1.0.1)
+- **Framework**: (e.g., Next.js 14, Vite + React)
+
+## Logs / Screenshots
+
+```
+Paste any relevant error output here
+```

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,23 @@
+---
+name: Feature Request
+about: Suggest a new feature or improvement
+title: ''
+labels: enhancement
+assignees: ''
+---
+
+## Problem
+
+What problem does this feature solve?
+
+## Proposed Solution
+
+Describe the solution you'd like.
+
+## Alternatives Considered
+
+Any alternative approaches you've thought about.
+
+## Additional Context
+
+Any other context, screenshots, or examples.

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,23 @@
+## What
+
+Brief description of the change.
+
+## Why
+
+Why is this change needed?
+
+## How
+
+How was this implemented? Any notable design decisions?
+
+## Testing
+
+- [ ] `npm run lint` passes
+- [ ] `npm run typecheck` passes
+- [ ] `npm test` passes
+- [ ] Tested manually (if applicable)
+
+## Screenshots (if UI change)
+
+Before | After
+--- | ---

.github/workflows/ci.yml

@@ -24,6 +24,8 @@ jobs:
 
       - run: npx playwright install chromium --with-deps
 
+      - run: npm run lint
+
       - run: npm run typecheck
 
       - run: npm run build

.prettierignore

@@ -0,0 +1,3 @@
+dist/
+node_modules/
+*.tgz

.prettierrc

@@ -0,0 +1,7 @@
+{
+  "singleQuote": true,
+  "trailingComma": "all",
+  "printWidth": 120,
+  "tabWidth": 2,
+  "semi": true
+}

CONTRIBUTING.md

@@ -8,6 +8,10 @@ Thanks for your interest in contributing!
 git clone https://github.com/M00N7682/imugi.git
 cd imugi
 npm install
+
+# Playwright requires a browser binary for screenshot capture:
+npx playwright install chromium
+
 npm run build
 npm test
 ```
@@ -16,14 +20,16 @@ npm test
 
 1. Fork the repo and create a feature branch
 2. Make your changes
-3. Run `npm run typecheck` and `npm test` to verify
+3. Run the checks: `npm run lint && npm run typecheck && npm test`
 4. Submit a pull request
 
 ## Code style
 
 - TypeScript strict mode
 - ESM modules
 - No default exports (except CLI entry)
+- Formatting enforced by Prettier (`npm run format`)
+- Linting enforced by ESLint (`npm run lint`)
 
 ## Running tests
 
@@ -34,6 +40,12 @@ npm test
 # Watch mode
 npm run test:watch
 
+# Lint
+npm run lint
+
+# Format
+npm run format
+
 # Type check
 npm run typecheck
 ```

README.md

@@ -55,6 +55,9 @@ imugi uses **SSIM** (Structural Similarity) + **pixelmatch** + **Claude Vision**
 
 ```bash
 npm install -g imugi-ai
+
+# Playwright requires a browser binary — install Chromium:
+npx playwright install chromium
 ```
 
 ### Step 2: Add to your AI tool

eslint.config.js

@@ -0,0 +1,24 @@
+import eslint from '@eslint/js';
+import tseslint from 'typescript-eslint';
+import prettierConfig from 'eslint-config-prettier';
+
+export default tseslint.config(
+  eslint.configs.recommended,
+  ...tseslint.configs.recommended,
+  prettierConfig,
+  {
+    languageOptions: {
+      parserOptions: {
+        projectService: true,
+        tsconfigRootDir: import.meta.dirname,
+      },
+    },
+    rules: {
+      '@typescript-eslint/no-unused-vars': ['error', { argsIgnorePattern: '^_' }],
+      '@typescript-eslint/no-explicit-any': 'warn',
+    },
+  },
+  {
+    ignores: ['dist/', 'node_modules/', '*.config.*'],
+  },
+);