feat: R-minor-sensitive binary builds (full + iterative) (#84)

## Summary

Builds R-minor-sensitive CRAN packages once per installed R minor version (into per-minor S3 slots `…/contrib/<x.y>/`) and everything else once into the generic slot, driven by bincraft 4.2.0's ABI classifier. Both the full and iterative pipelines are covered.

## What's in here

**Detection / precompute**

- `local/r-minor-helpers.R` — pure `classify_from_metadata()` (NeedsCompilation / risky `LinkingTo`) + `parse_build_args()`, with unit tests.
- `local/packages-to-build.R` — adds a per-package `r_minor_sensitive` flag: cheap CRAN-metadata rules first, source download + `bincraft::needs_per_minor_recompile()` only for the ambiguous compiled subset (fail-safe to sensitive). Classified once per package, applied to all versions.

**Full build**

- `local/build-all.R` — passes the per-row `is_r_minor_sensitive` flag; new `--sensitive-only` mode builds just the risky subset.
- `.crow/build-all-versions-{amd64,arm64}.yaml` — install-deps persists the sensitive subset; build step runs a sensitive-only pass under each non-primary `/opt/R/*` minor; new step uploads the generic index plus a per-minor index for each minor.

**Iterative build**

- All 14 `.crow/process-updates-*.yaml` — primary pass uses `r_minor_detection = 'classifier'`; a sensitive-only multi-R pass builds risky updates under each other minor; per-minor index upload added.

**Tooling / housekeeping**

- Pins bincraft `v4.1.1` → `v4.2.0` across all workflows; removes the superseded standalone `build-r-minor-sensitive-packages.yaml`.
- Adds prek/pre-commit hooks (prettier, markdownlint, editorconfig-checker, yamllint, air) and applies them repo-wide; excludes the verbatim GPL `LICENSE.md` and auxiliary shell scripts.
- Design + implementation docs under `docs/superpowers/`.

## Requires before merge

- A `v4.2.0` git tag must be pushed on the bincraft repo (codefloe.com/rpkgs/bincraft) — the workflow install steps pin `@v4.2.0`. The full-build install-deps clones `main`, so it is unaffected.

Reviewed-on: #84

local/fetch-rebuild-packages-from-issue.R

@@ -1,15 +1,21 @@
 library(httr2, quietly = TRUE)
 
 forgejo_base <- "https://git.devxy.io/api/v1"
-repo         <- "devxy/build-cran-binaries"
-platform     <- Sys.getenv("PLATFORM")
-arch         <- Sys.getenv("ARCH")
-token        <- Sys.getenv("FORGEJO_TOKEN")
-output_file  <- Sys.getenv("REBUILD_PKG_LIST", "/tmp/rebuild_pkgs.txt")
+repo <- "devxy/build-cran-binaries"
+platform <- Sys.getenv("PLATFORM")
+arch <- Sys.getenv("ARCH")
+token <- Sys.getenv("FORGEJO_TOKEN")
+output_file <- Sys.getenv("REBUILD_PKG_LIST", "/tmp/rebuild_pkgs.txt")
 
-if (nchar(platform) == 0) stop("PLATFORM env var is not set")
-if (nchar(arch)     == 0) stop("ARCH env var is not set")
-if (nchar(token)    == 0) stop("FORGEJO_TOKEN env var is not set")
+if (nchar(platform) == 0) {
+  stop("PLATFORM env var is not set")
+}
+if (nchar(arch) == 0) {
+  stop("ARCH env var is not set")
+}
+if (nchar(token) == 0) {
+  stop("FORGEJO_TOKEN env var is not set")
+}
 
 os_family <- if (grepl("^ubuntu", platform)) {
   "Ubuntu"
@@ -21,12 +27,16 @@ os_family <- if (grepl("^ubuntu", platform)) {
   platform
 }
 
-issue_title <- sprintf("Missing package binaries for latest version (%s)", os_family)
+issue_title <- sprintf(
+  "Missing package binaries for latest version (%s)",
+  os_family
+)
 cat(sprintf("Searching for issue: %s\n", issue_title))
 
 search_url <- sprintf(
   "%s/repos/%s/issues?type=issues&state=open&q=%s&limit=50",
-  forgejo_base, repo,
+  forgejo_base,
+  repo,
   utils::URLencode(issue_title, reserved = TRUE)
 )
 search_resp <- request(search_url) |>
@@ -34,7 +44,9 @@ search_resp <- request(search_url) |>
   req_perform()
 
 issues <- resp_body_json(search_resp, simplifyVector = FALSE)
-match_idx <- which(vapply(issues, function(x) x$title, character(1)) == issue_title)
+match_idx <- which(
+  vapply(issues, function(x) x$title, character(1)) == issue_title
+)
 
 if (length(match_idx) == 0) {
   cat("No matching issue found - nothing to rebuild\n")
@@ -55,7 +67,10 @@ lines <- strsplit(body, "\n", fixed = TRUE)[[1]]
 plat_header <- sprintf("## %s", platform)
 plat_idx <- which(lines == plat_header)
 if (length(plat_idx) == 0) {
-  cat(sprintf("No section found for platform %s - nothing to rebuild\n", platform))
+  cat(sprintf(
+    "No section found for platform %s - nothing to rebuild\n",
+    platform
+  ))
   writeLines(character(0), output_file)
   q("no")
 }
@@ -64,7 +79,11 @@ if (length(plat_idx) == 0) {
 arch_pattern <- sprintf("^### %s ", arch)
 arch_idx <- which(grepl(arch_pattern, lines) & seq_along(lines) > plat_idx[1])
 if (length(arch_idx) == 0) {
-  cat(sprintf("No section found for arch %s under %s - nothing to rebuild\n", arch, platform))
+  cat(sprintf(
+    "No section found for arch %s under %s - nothing to rebuild\n",
+    arch,
+    platform
+  ))
   writeLines(character(0), output_file)
   q("no")
 }
@@ -82,6 +101,11 @@ pkg_lines <- section_lines[grepl("^- ", section_lines)]
 pkgs <- sub("^- ([^ ]+) \\(.*\\)$", "\\1", pkg_lines)
 pkgs <- pkgs[nchar(pkgs) > 0 & pkgs != "_None_"]
 
-cat(sprintf("Found %d rebuildable packages for %s/%s\n", length(pkgs), platform, arch))
+cat(sprintf(
+  "Found %d rebuildable packages for %s/%s\n",
+  length(pkgs),
+  platform,
+  arch
+))
 writeLines(pkgs, output_file)
 cat(sprintf("Wrote package list to %s\n", output_file))