Refactor files name

[sgueissa]

Renaming the mod.go files without touching the message package because it will need more work than just renaming the files.

[CLAassistant]

All committers have signed the CLA.

[github-actions]

Pull reviewers stats

Stats of the last 30 days for popstellar:

	User	Total reviews	Time to review	Total comments
	pierluca 🥇	5 ▀▀▀	2d 6h 18m ▀▀	8 ▀▀▀▀
	MariemBaccari 🥈	5 ▀▀▀	1d 17h 15m ▀	1 ▀
	sgueissa 🥉	2 ▀	4d 21h 28m ▀▀▀▀	8 ▀▀▀▀
	jbsv	2 ▀	1d 7h 33m ▀	0
	arnauds5	1 ▀	6h 55m	0
	osm-alt	1 ▀	5h 52m	0
	ljankoschek	1 ▀	20h 9m ▀	0
	K1li4nL	1 ▀	18m	0
	emonnin-epfl	1 ▀	6h 45m	1 ▀

[sonarqubecloud]

Quality Gate passed for 'PoP - PoPCHA-Web-Client'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[sonarqubecloud]

Quality Gate passed for 'PoP - Be2-Scala'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[sonarqubecloud]

Quality Gate passed for 'PoP - Be1-Go'

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
81.5% Coverage on New Code
6.8% Duplication on New Code

See analysis details on SonarCloud

[sonarqubecloud]

Quality Gate passed for 'PoP - Fe2-Android'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[sonarqubecloud]

Quality Gate passed for 'PoP - Fe1-Web'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[emonnin-epfl]

LGTM!

[MariemBaccari]

I can see some changes inside files but I assume it's because of some automatic IDE formatting issue. Assuming you just renamed the file, the PR looks good to me, good job!