Implement steps 3 + 4 of issue #115 on top of the failure classifier, now
that bincraft v4.4.3 applies registry patches/makevars/configure_args to the
target build (not just dependencies), so a trial patched build is meaningful.
- refactor the classify helpers to expose a pure build_triage_report() and a
list-returning entry builder; failing-builds-report.R now renders from it
- add local/propose-patches.R (step 3, "propose, do not apply"): emit a
pre-filled registry.json entry for each classified, safe, unregistered
failure, validate the candidate set against a temporary merged registry,
and (only on request) --write it plus a proposals ledger, or --open-issue a
Forgejo tracking issue; the human gate and validator/trial-build acceptance
stay, and novel source diffs / unknown signatures are never proposed
- add local/trial-build-patch.R: isolated bincraft build of one package with
the registry applied (no upload/archive/metadata) as the pre-merge gate
- add local/proposal-tracking.R + local/proposal-tracking-lib.R (step 4):
signature hit rate, proposed-vs-merged, and retirement candidates, with the
pure helpers covered by tests
- teach validate-patches.R optional PATCH_DIR/REGISTRY_FILE overrides so a
candidate registry can be validated without touching the real one
- document the propose/trial-build/tracking workflow in local/patches/README.md
## Summary
Adds the curated **patch registry** and wiring that drives bincraft's new package-patching mechanism (see bincraft PR `feat/package-patching`).
Lets specific packages be patched (env/configure/Makevars overrides or source diffs) before pak installs them — including as transitive dependencies — so compiler-/OS-specific failures like RcppParallel's bundled TBB stop cascading.
## What's included
- `local/patches/registry.json` — initial entry: RcppParallel with `RCPP_PARALLEL_USE_TBB=0` for alpine / ubuntu-2604, plus `local/patches/README.md` schema docs.
- `local/validate-patches.R` — validates schema, referenced patch files, and ambiguous overlaps; clean failure + exit 1 (no stacktrace).
- `.pre-commit-config.yaml` — a `validate-patches` hook (re-runs when the registry or the validator changes).
- `local/build-one.R` / `local/build-all.R` — pass `patches = "local/patches"` to `bincraft::build_binary_package()`.
- `specs/2026-06-30-package-patching-design.md` and `plans/2026-06-30-package-patching-implementation.md`.
## ⚠️ Merge ordering (blocker)
This PR adds a `patches = ...` argument to `build_binary_package()` calls.
The `.crow/*.yaml` workflows currently pin bincraft **v4.2.3**, which does not accept that argument — CI will error with `unused argument (patches=...)` until:
1. bincraft **v4.3.0** is released (PR `feat/package-patching`), and
2. the pin is bumped in `.crow/build-all-versions-install-deps.yaml`, `.crow/build-all-versions.yaml`, and `.crow/process-updates.yaml`.
The `.crow` pin bump will be added to this PR once bincraft v4.3.0 is tagged. Do not merge before then.
Reviewed-on: #103
