ctcloud: CertSpotter-backed CT cloud-resource monitor

Single stateless Go process that consumes CT logs via embedded (patched)
CertSpotter internals, classifies cloud/database/storage DNS identifiers
in-process with a zero-allocation classifier, enriches via round-robin DNS
resolvers with CNAME following, and batch-writes useful findings to PostgreSQL.

- third_party/certspotter: 2-hunk IdentifierSink patch, no stdout/JSON/files
- internal/classify: AWS/Azure/GCP/Firebase/Cloudflare R2/DigitalOcean/Supabase/OCI
- internal/dns: sharded bounded TTL cache, multi-resolver load balancing + failover
- internal/pipeline: bounded queues, dedup, direct-priority load shedding
- internal/store: pgx batch writer, Postgres CT checkpoints (no cert contents)
- internal/probe: optional non-destructive reachability checks (off by default)
- Docker: distroless non-root, read-only rootfs, no app volume, resource limits
- tests enforce 0 allocs/op on the classifier and sink hot path

third_party/certspotter/canonicalize_test.go

@@ -0,0 +1,49 @@
+// Copyright (C) 2019 Opsmate, Inc.
+//
+// This Source Code Form is subject to the terms of the Mozilla
+// Public License, v. 2.0. If a copy of the MPL was not distributed
+// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+//
+// This software is distributed WITHOUT A WARRANTY OF ANY KIND.
+// See the Mozilla Public License for details.
+
+package certspotter
+
+import (
+	"testing"
+)
+
+type stringCanonTest struct {
+	in  string
+	out string
+}
+
+var stringCanonTests = []stringCanonTest{
+	{"", ""},
+	{" ", ""},
+	{"  ", ""},
+	{"abc", "abc"},
+	{"aBc", "abc"},
+	{"ab c", "ab c"},
+	{"ab  c", "ab c"},
+	{"ab\n c", "ab c"},
+	{" ab c ", "ab c"},
+	{" ab  c ", "ab c"},
+	{" ab  c", "ab c"},
+	{"ab  c ", "ab c"},
+	{"abc ", "abc"},
+	{"abc  ", "abc"},
+	{"  abc  ", "abc"},
+	{"  abc ", "abc"},
+	{"  abc", "abc"},
+	{"  aBc de  f      g\n", "abc de f g"},
+}
+
+func TestCanonicalizeRDNString(t *testing.T) {
+	for i, test := range stringCanonTests {
+		ret := canonicalizeRDNString(test.in)
+		if test.out != ret {
+			t.Errorf("#%d: canonicalizeRDNString(%q) = %q, want %q", i, test.in, ret, test.out)
+		}
+	}
+}