## Motivation
Build jobs were cycling through hundreds of packages that were only ever printed as `Skipping … due to previous build error recorded in metadata DB`, wasting wall-clock on per-package preparation before dropping each one.
## Cause
The prefilter query in `local/build-all.R` selected only successfully-built versions (`error_occurred = FALSE`) into `built`, so line 112 removed only those from the chunk.
Every previously-errored version stayed in the work list and was walked one-by-one, each hitting the internal skip in `build_binary_package()`.
This also explains the misleading `Skipped 0 already-built package versions` line for alphabetical chunks whose leading packages only have error records.
## Changes
- `local/build-all.R`: drop the `AND error_occurred = FALSE` clause so `built` holds every version already attempted (built or errored) for this platform/arch; the existing filter then removes all of them up front.
- Rename the log line to `already-attempted` so the reported count reflects successes and errors.
- Update the surrounding comment to explain why errored versions are excluded.
## Behaviour change
Previously-errored versions are now dropped before the build loop instead of being iterated and individually skipped.
No package that would otherwise build is affected, `build_binary_package()` already skipped these internally.
Retrying errored versions is out of scope and would need a separate opt-in flag on both the prefilter and the in-loop skip.
Reviewed-on: #113