GroupVerify: Verification page, overrides and public Verified tags

Shown only where GroupVerify is: staff get the Verification page once its gv_* tables are in
the database, and the public site shows "Verified" only while it's on (enabled, with a group)
and not missing from css_plugins list, which the poller reads once a minute over RCON.

- Verification page: plugin state and version, Steam group, saved member list, overrides.
- Overrides (@zio/verify, not on yourself unless Root): give, change, remove; player drawer
  shows why a player is or isn't verified.
- Root sets the group and turns it on/off: saved to gv_settings, and sent as css_gv_* when the
  plugin is loaded so it applies at once.
- gv_* times use GroupVerify's own timezone setting.
- MySQL integration test (SAW_TEST_DSN), unit tests for plugin list parsing and the show rule.

internal/web/verify_test.go

@@ -0,0 +1,43 @@
+package web
+
+import (
+	"testing"
+
+	"git.zio.sh/cs2/simpleadmin-web/internal/live"
+	"git.zio.sh/cs2/simpleadmin-web/internal/store"
+)
+
+func TestIsClanID(t *testing.T) {
+	for _, c := range []struct {
+		id   uint64
+		want bool
+	}{
+		{103582791429521412, true},  // a group
+		{103582791429521408, false}, // account 0
+		{76561198012345678, false},  // a player
+		{0, false},
+	} {
+		if got := isClanID(c.id); got != c.want {
+			t.Errorf("isClanID(%d) = %v, want %v", c.id, got, c.want)
+		}
+	}
+}
+
+func TestVerifyShown(t *testing.T) {
+	on := store.VerifySettings{Enabled: true, GroupID: "103582791429521412"}
+	for _, c := range []struct {
+		info verifyInfo
+		want bool
+	}{
+		{verifyInfo{Tables: true, Settings: on, Plugin: live.PluginLoaded}, true},
+		{verifyInfo{Tables: true, Settings: on, Plugin: live.PluginUnknown}, true},
+		{verifyInfo{Tables: true, Settings: on, Plugin: live.PluginMissing}, false},
+		{verifyInfo{Tables: false, Settings: on, Plugin: live.PluginLoaded}, false},
+		{verifyInfo{Tables: true, Settings: store.VerifySettings{Enabled: false, GroupID: on.GroupID}, Plugin: live.PluginLoaded}, false},
+		{verifyInfo{Tables: true, Settings: store.VerifySettings{Enabled: true}, Plugin: live.PluginLoaded}, false},
+	} {
+		if got := c.info.Shown(); got != c.want {
+			t.Errorf("%+v: Shown() = %v, want %v", c.info, got, c.want)
+		}
+	}
+}