Default sundry items are missing from project and should be added

[seidior]

Describe the Feature / Enhancement

The following items should be added to (or modified in) the project, but aren't large enough items to warrant an issue by themselves:

• .editorconfig - Configuration file for code style, supported by multiple IDEs.
• eslint.config.js - An ESLint configuration file, to ensure quality standards.
• .gitignore - We have one, but it should be enhanced to be similar to the incoming .dockerignore file.
• .npmrc - Basic NPM configuration, which applies to Yarn and PNPM, if we go either of those routes.
• .prettierrc - A Prettier configuration file for automatic code style fixes.
• .vscode/ - A folder of files with suggested extensions / settings for development in Visual Studio Code.
• CODE_OF_CONDUCT.md - The code of conduct for the repository.
• CONTRIBUTING.md - The contributing guidelines for all repository contributors.
• SECURITY.md - The security policy for the GitHub project.

Additional Details and Resources

package.json, README.md, and tsconfig.json will all come from whichever ticket lands switching us to Next.js, so we can wait on that in case we need to modify these.

Additional optional packages/technologies worth considering:

• Alex for insensitive/inconsiderate writing.
• Devcontainers for consistent development environments.
• Husky for installing git hooks automatically.

Correct Project Selected

• [x] This issue is linked to the appropriate project.

Labels

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[seidior]

Switching eslint.config.js to .eslintrc.cjs, since typescript-eslint doesn't yet support the new flat file syntax for ESLint configuration.

Also, any of the other files that are CommonJS (ESLint configuration, PostCSS configuration, Tailwind CSS configuration) should be renamed to .cjs, and any files that are ESModule syntax should be renamed .mjs.