feat: add canary, tcping, archive, resolve plugins

canary: generate realistic fake credentials (token/aws/basic) for
planting as canary tripwires. Per-channel state persistence.

tcping: TCP connect latency probe through SOCKS5 proxy with
min/avg/max reporting. Proxy-compatible alternative to traceroute.

archive: save URLs to Wayback Machine via Save Page Now API,
routed through SOCKS5 proxy.

resolve: bulk DNS resolution (up to 10 hosts) via TCP DNS through
SOCKS5 proxy with concurrent asyncio.gather.

83 new tests (1010 total), docs updated.

tests/test_archive.py

@@ -0,0 +1,150 @@
+"""Tests for the Wayback Machine archive plugin."""
+
+import asyncio
+import importlib.util
+import sys
+import urllib.error
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+from derp.irc import Message
+
+# plugins/ is not a Python package -- load the module from file path
+_spec = importlib.util.spec_from_file_location(
+    "plugins.archive", Path(__file__).resolve().parent.parent / "plugins" / "archive.py",
+)
+_mod = importlib.util.module_from_spec(_spec)
+sys.modules[_spec.name] = _mod
+_spec.loader.exec_module(_mod)
+
+from plugins.archive import _save_page, cmd_archive  # noqa: E402
+
+# -- Helpers -----------------------------------------------------------------
+
+class _FakeBot:
+    def __init__(self):
+        self.replied: list[str] = []
+
+    async def reply(self, message, text: str) -> None:
+        self.replied.append(text)
+
+
+def _msg(text: str) -> Message:
+    return Message(
+        raw="", prefix="alice!~alice@host", nick="alice",
+        command="PRIVMSG", params=["#test", text], tags={},
+    )
+
+
+# -- _save_page --------------------------------------------------------------
+
+class TestSavePage:
+    def test_content_location_header(self):
+        resp = MagicMock()
+        resp.headers = {"Content-Location": "/web/20260220/https://example.com"}
+        resp.read.return_value = b""
+        resp.geturl.return_value = "https://web.archive.org/save/https://example.com"
+
+        with patch.object(_mod, "_urlopen", return_value=resp):
+            result = _save_page("https://example.com")
+
+        assert "url" in result
+        assert "/web/20260220" in result["url"]
+
+    def test_final_url_redirect(self):
+        resp = MagicMock()
+        resp.headers = {}
+        resp.read.return_value = b""
+        resp.geturl.return_value = "https://web.archive.org/web/20260220/https://example.com"
+
+        with patch.object(_mod, "_urlopen", return_value=resp):
+            result = _save_page("https://example.com")
+
+        assert "url" in result
+        assert "/web/20260220" in result["url"]
+
+    def test_fallback_url(self):
+        resp = MagicMock()
+        resp.headers = {}
+        resp.read.return_value = b""
+        resp.geturl.return_value = "https://web.archive.org/save/ok"
+
+        with patch.object(_mod, "_urlopen", return_value=resp):
+            result = _save_page("https://example.com")
+
+        assert "url" in result
+        assert "/web/*/" in result["url"]
+
+    def test_rate_limit(self):
+        exc = urllib.error.HTTPError(
+            "url", 429, "Too Many Requests", {}, None,
+        )
+        with patch.object(_mod, "_urlopen", side_effect=exc):
+            result = _save_page("https://example.com")
+
+        assert "error" in result
+        assert "rate limit" in result["error"]
+
+    def test_origin_unreachable(self):
+        exc = urllib.error.HTTPError(
+            "url", 523, "Origin Unreachable", {}, None,
+        )
+        with patch.object(_mod, "_urlopen", side_effect=exc):
+            result = _save_page("https://example.com")
+
+        assert "error" in result
+        assert "unreachable" in result["error"]
+
+    def test_generic_http_error(self):
+        exc = urllib.error.HTTPError(
+            "url", 500, "Server Error", {}, None,
+        )
+        with patch.object(_mod, "_urlopen", side_effect=exc):
+            result = _save_page("https://example.com")
+
+        assert "error" in result
+        assert "500" in result["error"]
+
+    def test_timeout(self):
+        with patch.object(_mod, "_urlopen", side_effect=TimeoutError("timed out")):
+            result = _save_page("https://example.com")
+
+        assert "error" in result
+        assert "timeout" in result["error"]
+
+
+# -- Command handler ---------------------------------------------------------
+
+class TestCmdArchive:
+    def test_no_args(self):
+        bot = _FakeBot()
+        asyncio.run(cmd_archive(bot, _msg("!archive")))
+        assert "Usage" in bot.replied[0]
+
+    def test_no_scheme(self):
+        bot = _FakeBot()
+        asyncio.run(cmd_archive(bot, _msg("!archive example.com")))
+        assert "http://" in bot.replied[0]
+
+    def test_success(self):
+        bot = _FakeBot()
+        result = {"url": "https://web.archive.org/web/20260220/https://example.com"}
+
+        with patch.object(_mod, "_save_page", return_value=result):
+            asyncio.run(cmd_archive(bot, _msg("!archive https://example.com")))
+
+        assert len(bot.replied) == 2
+        assert "Archiving" in bot.replied[0]
+        assert "Archived:" in bot.replied[1]
+        assert "/web/20260220" in bot.replied[1]
+
+    def test_error(self):
+        bot = _FakeBot()
+        result = {"error": "rate limited -- try again later"}
+
+        with patch.object(_mod, "_save_page", return_value=result):
+            asyncio.run(cmd_archive(bot, _msg("!archive https://example.com")))
+
+        assert len(bot.replied) == 2
+        assert "failed" in bot.replied[1].lower()
+        assert "rate limit" in bot.replied[1]