Rewrite remembering in Go

The shell pipeline (sed | sort | tee | awk | sort | cut | "$@"
plus the cut | uniq | awk profile rewrite) becomes a single static
binary with the same observable behaviour, pinned by the original
ranking.sh, signals.sh and cli-opts.sh suites, now aimed at
remembering.bin:

- the profile keeps the exact on-disk format, COUNT profile TEXT,
  byte-sorted with new picks appended at 1 and offered-but-never-
  picked entries persisted at 0;
- the menu stays count-descending with byte-order ties, stdin
  alone defines what is offered, and duplicate profile lines sum
  for ranking but collapse to the highest count on rewrite, as
  sort | uniq -f1 did;
- the wrapped command's exit status is forwarded as-is (128+sig
  for signal deaths), its stderr passes through, and an empty pick
  learns nothing;
- the profile rewrite stays atomic via .tmp plus rename.

Per the house CLI conventions, -h/-V/--help/--version are gone
(the manpage is the documentation; bad options print the usage on
stderr and exit 2), and getopts-style attached option arguments
(-pNAME) are not accepted any more --- no script in the wild used
them.

The project layout follows rot: raw go tool compile/link Makefile,
mkdeps.sh-generated deps.mk, white-box unit suite, fuzz target
over the profile parse/serialize roundtrip, functional pick
roundtrip, a 1M-line ranking benchmark, and a single English
asciidoc manpage absorbing the old .5 page; the po4a/aux release
machinery goes away.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

2 files changed, 83 insertions, 0 deletions

diff --git a/tests/benchmarks/ranking-throughput/main.go b/tests/benchmarks/ranking-throughput/main.go
new file mode 100644
index 0000000..0b02dc7
--- /dev/null
+++ b/tests/benchmarks/ranking-throughput/main.go
@@ -0,0 +1,7 @@
+package main
+
+import "remembering"
+
+func main() {
+	remembering.MainTest()
+}
diff --git a/tests/benchmarks/ranking-throughput/remembering.go b/tests/benchmarks/ranking-throughput/remembering.go
new file mode 100644
index 0000000..041eaeb
--- /dev/null
+++ b/tests/benchmarks/ranking-throughput/remembering.go
@@ -0,0 +1,76 @@
+package remembering
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+
+
+var linesFlag = flag.Int(
+	"lines",
+	1000000,
+	"The number of menu lines to rank",
+)
+
+func MainTest() {
+	flag.Parse()
+	n := *linesFlag
+
+	tmp, err := os.MkdirTemp("", "remembering-bench-")
+	if err != nil {
+		panic(err)
+	}
+	defer os.RemoveAll(tmp)
+	err = os.Setenv("XDG_DATA_HOME", tmp)
+	if err != nil {
+		panic(err)
+	}
+
+	menu := strings.Builder{}
+	for i := 0; i < n; i++ {
+		fmt.Fprintf(&menu, "item-%07d\n", i)
+	}
+
+	// half the items are already known, with spread counts
+	profile := strings.Builder{}
+	for i := 0; i < n; i += 2 {
+		fmt.Fprintf(
+			&profile, "%d profile item-%07d\n",
+			i%97, i,
+		)
+	}
+	path, err := profilePath("bench")
+	if err != nil {
+		panic(err)
+	}
+	err = os.MkdirAll(filepath.Dir(path), 0755)
+	if err != nil {
+		panic(err)
+	}
+	err = os.WriteFile(
+		path, []byte(profile.String()), 0644,
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	rc := run(envT{
+		allArgs: []string{
+			"remembering", "-p", "bench",
+			"--", "tail", "-n1",
+		},
+		in:  strings.NewReader(menu.String()),
+		out: io.Discard,
+		err: os.Stderr,
+	})
+	if rc != 0 {
+		panic("ranking failed")
+	}
+
+	fmt.Printf("ranked %d lines\n", n)
+}