Name request log actions so they say what they mean (closes #229)

The request log's `action` values now say what they mean, as sneak named them: `request_header_too_large`, `client_is_rate_limited`, `blocked_by_block_rule` and `client_denied`, with no aliases. `banned` splits into `temporarily_banned` and `permanently_banned`, by whether the ban runs out. When a permanent ban also covers a client, that ban is the one reported.

Trips a reader: a request over a rate limit stays `client_is_rate_limited` even when the ban it makes is permanent.
Disclosure: the offence key `rule_blocked` is renamed in `clients.json` too, so an existing file holding it stops the start and must be removed. Its `version` stays 1.

Model: opus-5-5

internal/discriminator/alerts_test.go

@@ -31,14 +31,14 @@ func TestBanForABrokenLimitRaisesABanAlertWithItsNotes(t *testing.T) {
 	start := clk.Now()
 
 	s.get(client, http.StatusOK, requestlog.ActionForward)
-	s.get(client, http.StatusForbidden, requestlog.ActionRateLimited)
+	s.get(client, http.StatusForbidden, requestlog.ActionClientIsRateLimited)
 
 	netblock := netip.MustParsePrefix("203.0.113.0/24")
 	ban := server.Ledger.Bans(netblock)[0]
 
 	// A request refused under the ban raises no other alert.
 	clk.advance(time.Minute)
-	s.get(client, http.StatusForbidden, requestlog.ActionBanned)
+	s.get(client, http.StatusForbidden, requestlog.ActionTemporarilyBanned)
 
 	wantAlerts(t, queue, banAlert(alerts.EventBan, start, client, bans.Ban{
 		Netblock: netblock, Cause: bans.CauseLimit,
@@ -62,22 +62,24 @@ func TestAttackBanRaisesABanAlertThenAPermanentBanAlert(t *testing.T) {
 
 	// The probe bans the client for seven days, and its next request makes
 	// the ban permanent. The request after that changes nothing.
-	s.request(client, "/.env", http.StatusForbidden, requestlog.ActionBanned)
+	s.request(client, "/.env", http.StatusForbidden, requestlog.ActionTemporarilyBanned)
 
 	attackBan := server.Ledger.Bans(netblock)[0]
 
 	clk.advance(time.Minute)
-	s.get(client, http.StatusForbidden, requestlog.ActionBanned)
+	s.get(client, http.StatusForbidden, requestlog.ActionPermanentlyBanned)
 
 	permanentBan := server.Ledger.Bans(netblock)[0]
 
-	s.get(client, http.StatusForbidden, requestlog.ActionBanned)
+	s.get(client, http.StatusForbidden, requestlog.ActionPermanentlyBanned)
 
 	// Another client's probe after its first ban has run out without a
 	// request makes a permanent ban at once.
-	s.request(otherClient, "/.env", http.StatusForbidden, requestlog.ActionBanned)
+	s.request(otherClient, "/.env", http.StatusForbidden,
+		requestlog.ActionTemporarilyBanned)
 	clk.advance(7 * 24 * time.Hour)
-	s.request(otherClient, "/.env", http.StatusForbidden, requestlog.ActionBanned)
+	s.request(otherClient, "/.env", http.StatusForbidden,
+		requestlog.ActionPermanentlyBanned)
 
 	otherBans := server.Ledger.Bans(other)