chore: Update ESLint to v9.39.5

[ysknsid25]

resolves: #174

Summary by CodeRabbit

• Chores
  • Upgraded the website’s linting setup to ESLint 9.
  • Added modern JavaScript, TypeScript, and Qwik linting presets.
  • Consolidated linting configuration into a flat configuration format.
  • Updated TypeScript project configuration to recognize the new lint setup.
  • Refreshed linting dependencies and project-wide environment settings.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Run ID: bb579e66-9958-43d6-9254-de069db6c7b2

📥 Commits

Reviewing files that changed from the base of the PR and between 426ad7e and 8229b80.

⛔ Files ignored due to path filters (1)

• pnpm-lock.yaml is excluded by !**/pnpm-lock.yaml

📒 Files selected for processing (1)

• website/package.json

💤 Files with no reviewable changes (1)

• website/package.json

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Walkthrough

The website migrated from ESLint 8 legacy configuration to ESLint 9 flat configuration. The new configuration includes JavaScript, TypeScript, and Qwik presets, project-wide ignores, environment globals, TypeScript project-service parsing, JSX support, and project-specific rules. The package metadata adds the required ESLint packages, removes @types/eslint, and updates ESLint. TypeScript now references eslint.config.js.

Possibly related PRs

• open-circle/formisch#113: Migrates ESLint setup to flat configuration and adds website linting.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly identifies the primary change: upgrading ESLint to version 9.39.5.
Linked Issues check	✅ Passed	The changes replace ESLint 8.57.1 with 9.39.5 and migrate the website configuration to ESLint 9.
Out of Scope Changes check	✅ Passed	All reviewed changes support the ESLint 9 upgrade and related configuration migration.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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[Copilot]

Pull request overview

This PR updates the website workspace lint tooling to ESLint v9.39.5 and migrates configuration from legacy .eslintrc/.eslintignore to an ESLint flat config (eslint.config.js), aligning with ESLint v9’s recommended setup and addressing the deprecated eslint@8.57.1 warning in issue #174.

Changes:

• Upgraded website devDependencies to ESLint ^9.39.5 and added supporting flat-config dependencies (@eslint/js, globals, typescript-eslint).
• Replaced website/.eslintrc.cjs and website/.eslintignore with a new website/eslint.config.js flat config.
• Updated website/tsconfig.json to include the new ESLint config file, and refreshed pnpm-lock.yaml.

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
website/tsconfig.json	Updates TS project files list to reference eslint.config.js instead of the removed .eslintrc.cjs.
website/package.json	Bumps ESLint to v9 and adds flat-config-related devDependencies.
website/eslint.config.js	Introduces ESLint v9 flat configuration with global ignores, TS + Qwik presets, and local rule overrides.
website/.eslintrc.cjs	Removes legacy ESLint config (replaced by flat config).
website/.eslintignore	Removes legacy ignore file (replaced by flat config ignores).
pnpm-lock.yaml	Lockfile updates reflecting ESLint v9 and dependency changes.

Files not reviewed (1)

• pnpm-lock.yaml: Generated file

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[cubic-dev-ai]

All reported issues were addressed across 6 files

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