Doodba migration plan

Plan an Odoo version upgrade. Upload your current addons.yaml, pick a "From" and "To" version, and for every step in between see what it should look like — plus a repos.yaml for anything not merged upstream yet. Dependencies get re-resolved at each version, so a module you never listed can still turn up if something you do use pulls it in there. Modules that are known but not merged anywhere, with no PR open, show up as missing — that's what's actually blocking the jump. Modules never seen before show up as unknown: not a red flag, just a blind spot. repos.yaml only lists what doodba's base config doesn't already cover — open PRs/MRs and anything outside OCA/odoo. Up to 500 modules per request.