docs: add migration docs (#78)

* migration docs added

* adding docs cos cannot interleave

* adding comments

* Update docs/how-to/integrate-da.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* Update docs/how-to/migrate/forkid-7-to-9.md

Co-authored-by: Léo Vincent <[email protected]>

* updates after review

* last step amend

* docs: update fork migration

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Co-authored-by: Léo Vincent <[email protected]>
Co-authored-by: leovct <[email protected]>