Land the v0.1 editor integration: the git_sync module (libgit2 on the SD
/sd/repo, dedicated 96KB git thread, lazy Wi-Fi, :sync push with
synced/up-to-date/failed snackbars), the boot splash (Spike 9) plus its bin
and justfile recipes, and a power-on→cursor boot-timing log. Also re-syncs
the roadmap/spikes/v0.1-product status and adds the SD hardware reference
photo.
Graduate the proven Spike 3 storage stack into firmware::persistence so the
editor and the spike share one implementation. Storage::mount brings up the
dedicated SPI3 bus (ADR-012) and mounts FAT with format_if_mount_failed=false
(never reformat the user's card). save() does the FAT-safe atomic write
(tmp -> fsync -> unlink -> rename); recover() reconciles a leftover *.tmp at
boot, keeping the committed file when the crash point is ambiguous and only
promoting the tmp when the target was already unlinked. load() caps reads at
256 KiB.
The single-shot connect_wifi aborted boot on any transient association or
DHCP miss — common right after a reset, when the AP still holds the stale
pre-reset association. Add a bounded retry (5 attempts, 500ms→4s backoff,
disconnect between tries) so those transient failures recover instead of
failing the boot.
Extract the logic into firmware::net (new lib target) and rewire the
wifi_tls / git_push / git_sync spikes to it, removing three duplicated
copies. main.rs reuses this when Wi-Fi lands there instead of adding a
fourth copy.
