release: 1.9.2: Review pass: port-25 milters, DMARC validation, rate-limit fix

Review pass over `1.4.0`…`1.9.1`: port 25 no longer shares the submission milter chain, DMARC reports are validated before they are stored, and the auto rate limit is correct for a non-default level-1 window. Schema migration `0010` (index only). Upgrading is a tag bump.
Added:
  - SQLite migration `0010_send_log_app_login_index.sql` —
  - DMARC aggregate reports are accepted as **zip** as well as gzip or plain XML
  - e2e: `checkPort25ConfigCombinations` regenerates the Postfix configuration
Changed:
  - README hero line and a **Positioning** block in `docs/product.md` record the
Fixed:
  - The setup account's password is hashed at bcrypt cost `12` like every other
  - Login/setup rate limiter: protecting blocked buckets from eviction is now
  - `postqueue -p` output is bounded to 4 MiB (the timeout alone left the size of
  - [schema-migrations.md](docs/schema-migrations.md): the schema section was
  - postqueue reader is now time-bounded: `postqueue -p` runs under a 5-second
  … (11 more in CHANGELOG)
Changed:
  - [roadmap.md](docs/roadmap.md) now carries everything the 2026-08-19 code
  - Extracted `internal/configsafe` — the empty-value and forbidden-character
  - Build, deploy and migration comments no longer cite the archived
  - Dropped the `parseDomainRateLimitForm` / `parseAppRateLimitForm` pass-through
  - Extracted shared helpers: `internal/atomicfile` (atomic temp-write+rename) and
  … (7 more in CHANGELOG)
Removed:
  - Unused legacy asset `docs/assets/icon.png` (superseded by the four brand SVGs
  - Plan documents for already-shipped features: `domain-stats-auto-ratelimit`,

Full detail: CHANGELOG.md (1.9.2).

internal/domain/opendkim.go

@@ -5,10 +5,13 @@ import (
 	"encoding/pem"
 	"fmt"
 	"os"
-	"os/exec"
+	"path"
 	"path/filepath"
 	"sort"
 	"strings"
+
+	"github.com/mixeme/selfpost/internal/configsafe"
+	"github.com/mixeme/selfpost/internal/supervisor"
 )
 
 // OpenDKIM manages the on-disk OpenDKIM state the panel is responsible for
@@ -191,7 +194,7 @@ func renderTables(keysDir string, domains []SigningDomain) (keyTable, signingTab
 		}
 		keyName := d.Name // one key per domain; the domain name is a fine handle
 		// Absolute key path so OpenDKIM resolves it independently of its CWD.
-		keyFile := filepath.Join(keysDir, d.Name, d.Selector+".private")
+		keyFile := path.Join(keysDir, d.Name, d.Selector+".private")
 		// KeyTable:     <key-name>  <domain>:<selector>:<key-path>
 		fmt.Fprintf(&kt, "%s %s:%s:%s\n", keyName, d.Name, d.Selector, keyFile)
 		// SigningTable (refile): <address-pattern>  <key-name>
@@ -200,18 +203,23 @@ func renderTables(keysDir string, domains []SigningDomain) (keyTable, signingTab
 	return []byte(kt.String()), []byte(st.String()), nil
 }
 
+// opendkimForbidden is what may never appear in a KeyTable or SigningTable
+// value: whitespace and the newline that would end the line, and the colon and
+// path separators that carry meaning inside a table entry.
+const opendkimForbidden = " \t\r\n:/\\"
+
 // assertConfigSafe rejects any domain/selector value that could break out of a
 // single table line. Domains are already whitelisted to [a-z0-9.-] and selectors
 // to a similar set before they reach here (security.md); this is defence in depth
 // against a validation gap ever letting whitespace, a newline or a field
 // separator through into a config file (security.md).
 func assertConfigSafe(domainName, selector string) error {
-	for _, v := range []string{domainName, selector} {
-		if v == "" {
-			return fmt.Errorf("opendkim: empty domain or selector")
-		}
-		if strings.ContainsAny(v, " \t\r\n:/\\") {
-			return fmt.Errorf("opendkim: unsafe character in %q", v)
+	for _, f := range []struct{ what, value string }{
+		{"domain", domainName},
+		{"selector", selector},
+	} {
+		if err := configsafe.Token(f.what, f.value, opendkimForbidden); err != nil {
+			return fmt.Errorf("opendkim: %w", err)
 		}
 	}
 	return nil
@@ -226,12 +234,5 @@ func assertConfigSafe(domainName, selector string) error {
 // Arguments are fixed literals — no user input is interpolated into the command,
 // and it never goes through a shell (security.md).
 func reloadViaSupervisor() error {
-	cmd := exec.Command("supervisorctl",
-		"-c", "/etc/supervisor/supervisord.conf",
-		"signal", "USR1", "opendkim")
-	out, err := cmd.CombinedOutput()
-	if err != nil {
-		return fmt.Errorf("reload opendkim via supervisor: %w: %s", err, strings.TrimSpace(string(out)))
-	}
-	return nil
+	return supervisor.Signal("USR1", "opendkim")
 }