Add some ESLint rules + minor changes (#3665)

Main point was to enable ESLint `dot-notation` and `no-unneeded-ternary`
rules for more code consistency.

I took the occasion to add two minor commits:
- Fix a problem found by running `test:spelling
- Minor dependency update

It wouldn't be a problem if the PR didn't arrive in the next release,
the changes are cosmetic.

package-lock.json

@@ -24,10 +24,10 @@
 				"module-alias": "^2.2.3",
 				"moment": "^2.30.1",
 				"node-ical": "^0.20.1",
-				"pm2": "^5.4.2",
+				"pm2": "^5.4.3",
 				"socket.io": "^4.8.1",
 				"suncalc": "^1.9.0",
-				"systeminformation": "^5.23.23",
+				"systeminformation": "^5.23.24",
 				"undici": "^7.2.0"
 			},
 			"devDependencies": {
@@ -13084,9 +13084,9 @@
 			"license": "0BSD"
 		},
 		"node_modules/systeminformation": {
-			"version": "5.23.23",
-			"resolved": "https://registry.npmjs.org/systeminformation/-/systeminformation-5.23.23.tgz",
-			"integrity": "sha512-QhEWrMFZnzWjFZ7J65gikIXTrB8U6b7VTQ8pLaF/GUgJaJoUoSuucqalIVj91D/grhRUtXplL6qYwTn1A4FfhQ==",
+			"version": "5.23.24",
+			"resolved": "https://registry.npmjs.org/systeminformation/-/systeminformation-5.23.24.tgz",
+			"integrity": "sha512-dPEaqxCaOQMp+5/zCSjuGWbYW2NNBHUZZgI8SNs8xZbLSML2gXvf8OUiqr7Ea1zLkEuH3Tu58DLiNe4kwftPxw==",
 			"license": "MIT",
 			"os": [
 				"darwin",