Associate goals with sites, not domains

[aerosol]

Changes

With #2803, we've overlooked the fact that goals were being created with domain instead of site's foreign key. This PR addresses that. Requires a staged postgres migration partially introduced in #2833 first - only then I'll rebase this PR and re-enable goals creation.

Tests

• Automated tests have been added
• This PR does not require tests

Changelog

• Entry has been added to changelog
• This PR does not make a user-facing change

Documentation

• Docs have been updated
• This change does not need a documentation update

Dark mode

• The UI has been tested both in dark and light mode
• This PR does not change the UI

[bundlemon]

BundleMon

Unchanged files (7)

Status	Path	Size	Limits
✅	static/css/app.css	492.34KB	-
✅	static/js/dashboard.js	297.58KB	-
✅	static/js/app.js	12.13KB	-
✅	static/js/embed.host.js	5.58KB	-
✅	static/js/embed.content.js	5.06KB	-
✅	tracker/js/plausible.js	733B	-
✅	static/js/applyTheme.js	314B	-

No change in files bundle size

Final result: ✅

View report in BundleMon website ➡️

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Current branch size history | Target branch size history