Your issue is this:
4:09:11 PM: Treating warnings as errors because process.env.CI = true.
As it says, warnings in your build are being treated as errrors.
Your build throws a bunch of warnings about unused variables etc…
4:09:11 PM: Line 4:8: 'Header' is defined but never used no-unused-vars
4:09:11 PM: src/pages/Main.jsx
4:09:11 PM: Line 3:10: 'Link' is defined but never used no-unused-vars
4:09:11 PM: Line 20:11: img elements must have an alt prop, either with meaningful text, or an empty string for decorative images jsx-a11y/alt-text
4:09:11 PM: Line 34:11: The href attribute requires a valid value to be accessible. Provide a valid, navigable address as the href value. If you cannot provide a valid href, but still need the element to resemble a link, use a button and change it with appropriate styles. Learn more: https://github.com/jsx-eslint/eslint-plugin-jsx-a11y/blob/HEAD/docs/rules/anchor-is-valid.md jsx-a11y/anchor-is-valid
4:09:11 PM: Line 37:11: The href attribute requires a valid value to be accessible. Provide a valid, navigable address as the href value. If you cannot provide a valid href, but still need the element to resemble a link, use a button and change it with appropriate styles. Learn more: https://github.com/jsx-eslint/eslint-plugin-jsx-a11y/blob/HEAD/docs/rules/anchor-is-valid.md jsx-a11y/anchor-is-valid
4:09:11 PM: Line 40:11: The href attribute requires a valid value to be accessible. Provide a valid, navigable address as the href value. If you cannot provide a valid href, but still need the element to resemble a link, use a button and change it with appropriate styles. Learn more: https://github.com/jsx-eslint/eslint-plugin-jsx-a11y/blob/HEAD/docs/rules/anchor-is-valid.md jsx-a11y/anchor-is-valid
You could clean all those up, but you probably just want to turn the CI environment variable to false so that it no longer treats warnings as errors that cause the build to fail.
It’s mentioned at the bottom here:
The easiest way would be changing your Build Command from npm run build to CI= npm run build