cronr: recurring/one-shot jobs as systemd user timers

add (schedule validated by systemd-analyze, units + script printed),
list (next elapse + last result), run, logs, rm. Command stored as a
script so quoting never meets ExecStart; PATH includes ~/.local/bin
so agent tools resolve. cronr-* namespace guards foreign units.
Smoked live: add -> run -> journal -> rm. Spec: doc/tool-parity.md 3.1.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011KikHkfCiC3yELbsMN8fT9

cronr/unit/unit_test.go

@@ -0,0 +1,84 @@
+package unit
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestValidName(t *testing.T) {
+	for _, ok := range []string{"nightly-ci-check", "a", "Job_2", "x1-y2"} {
+		if !ValidName(ok) {
+			t.Errorf("%q should be valid", ok)
+		}
+	}
+	for _, bad := range []string{"", "-leading", "has space", "slash/y", "ä", strings.Repeat("x", 65), "dot.name"} {
+		if ValidName(bad) {
+			t.Errorf("%q should be invalid", bad)
+		}
+	}
+}
+
+func TestScriptKeepsCommandVerbatim(t *testing.T) {
+	cmd := `agy -p "check CI, say 'hi' & notify" | tee /tmp/x`
+	s := Script(cmd)
+	if !strings.HasPrefix(s, "#!/bin/sh\n") {
+		t.Error("missing shebang")
+	}
+	if !strings.Contains(s, cmd) {
+		t.Error("command was mangled")
+	}
+}
+
+func TestServiceUnit(t *testing.T) {
+	s := Service("nightly", "/home/x/.local/share/cronr/nightly.sh")
+	for _, want := range []string{
+		"Type=oneshot",
+		"ExecStart=/bin/sh /home/x/.local/share/cronr/nightly.sh",
+		"Environment=PATH=%h/.local/bin",
+	} {
+		if !strings.Contains(s, want) {
+			t.Errorf("service missing %q:\n%s", want, s)
+		}
+	}
+}
+
+func TestTimerUnit(t *testing.T) {
+	rec := Timer("nightly", "*-*-* 07:00", false)
+	if !strings.Contains(rec, "OnCalendar=*-*-* 07:00") || !strings.Contains(rec, "Persistent=true") {
+		t.Errorf("recurring timer wrong:\n%s", rec)
+	}
+	once := Timer("boot", "2026-08-06 03:00", true)
+	if !strings.Contains(once, "Persistent=false") {
+		t.Errorf("one-shot timer should not be persistent:\n%s", once)
+	}
+	if !strings.Contains(once, "WantedBy=timers.target") {
+		t.Error("timer missing install section")
+	}
+}
+
+func TestUnitAndJobNames(t *testing.T) {
+	svc, tmr := UnitNames("nightly")
+	if svc != "cronr-nightly.service" || tmr != "cronr-nightly.timer" {
+		t.Errorf("unit names: %s %s", svc, tmr)
+	}
+	if JobName("/home/x/.config/systemd/user/cronr-nightly.timer") != "nightly" {
+		t.Error("JobName failed on full path")
+	}
+	if JobName("helmd.service") != "" {
+		t.Error("foreign unit must not map to a job")
+	}
+}
+
+func TestAtToCalendar(t *testing.T) {
+	if _, err := AtToCalendar("2026-08-06 03:00"); err != nil {
+		t.Errorf("valid --at rejected: %v", err)
+	}
+	if _, err := AtToCalendar("2026-08-06 03:00:30"); err != nil {
+		t.Errorf("valid --at with seconds rejected: %v", err)
+	}
+	for _, bad := range []string{"imorgon", "03:00", "2026-8-6 03:00", "2026-08-06T03:00"} {
+		if _, err := AtToCalendar(bad); err == nil {
+			t.Errorf("bad --at %q accepted", bad)
+		}
+	}
+}