refactor!: Make `Actor` initialization stricter and more predictable #679

Job	Run time
Type check / Type check (3.13)	28s
Type check / Type check (3.12)	27s
Type check / Type check (3.11)	38s
Docs check / Docs check	1m 7s
Lint check / Lint check (3.10)	11s
Lint check / Lint check (3.11)	15s
Lint check / Lint check (3.12)	11s
Lint check / Lint check (3.13)	15s
Unit tests / Unit tests (windows-latest, 3.11)	48s
Unit tests / Unit tests (windows-latest, 3.13)	54s
Unit tests / Unit tests (ubuntu-latest, 3.11)	28s
Unit tests / Unit tests (ubuntu-latest, 3.13)	23s
Unit tests / Unit tests (ubuntu-latest, 3.10)	26s
Unit tests / Unit tests (windows-latest, 3.10)	1m 0s
Unit tests / Unit tests (ubuntu-latest, 3.12)	35s
Type check / Type check (3.10)	29s
Unit tests / Unit tests (windows-latest, 3.12)	50s
Integration tests / Integration tests (3.10)	10m 42s
Integration tests / Approve integration tests for PRs from forks	7m 32s
Integration tests / Integration tests (3.13)	10m 17s
Integration tests / Integration tests for PRs from forks	0s
	37m 56s

Provide feedback