Store a target's settings as columns (closes #543)

A target's settings move from the per-type JSON string in
targets.config to columns: url, headers, timeout_seconds,
forward_query, archive_expiry and archive_rotation. A column a type
does not use stays empty. headers holds the header map as JSON text
through GORM's JSON serializer, and archive_expiry holds a
time.Duration, 0 meaning never, so nothing that reads a target parses
it. The forms check each setting once, with the same refusals and
messages, and the edit form is filled from the columns, so the
per-type config structs, their parsers and the "could not be read"
branches are gone. A delivery task carries the six settings in place
of the JSON string.

Model: opus-5-5

internal/handlers/delivery_replay_test.go

@@ -192,7 +192,7 @@ func TestHandleDeliveryReplay_AppendsDeliveryAndLeavesOriginal(
 	wh := seedWebhook(t, db)
 	tgt := seedConfiguredTarget(
 		t, db, wh.ID, database.TargetTypeHTTP,
-		`{"url":"`+replayTargetURL+`"}`,
+		database.Target{URL: replayTargetURL},
 	)
 
 	event, original := seedFailedDelivery(
@@ -205,13 +205,13 @@ func TestHandleDeliveryReplay_AppendsDeliveryAndLeavesOriginal(
 	before := loadDelivery(t, webhookDB, original.ID)
 
 	// The operator fixes the destination, which is the whole reason
-	// to replay. The replay must use this, not the config the
-	// original delivery ran against.
-	const fixedConfig = `{"url":"http://93.184.216.34/fixed"}`
+	// to replay. The replay must use this, not the URL the original
+	// delivery ran against.
+	const fixedURL = "http://93.184.216.34/fixed"
 
 	require.NoError(t, db.DB().Model(&database.Target{}).
 		Where("id = ?", tgt.ID).
-		Update("config", fixedConfig).Error)
+		Update("url", fixedURL).Error)
 
 	w := postReplay(t, h, sess, wh.ID, original.ID)
 
@@ -240,7 +240,7 @@ func TestHandleDeliveryReplay_AppendsDeliveryAndLeavesOriginal(
 	tasks := notif.Tasks()
 	require.Len(t, tasks, 1)
 	assertReplayTask(
-		t, tasks[0], wh.ID, event, tgt, replayed.ID, fixedConfig,
+		t, tasks[0], wh.ID, event, tgt, replayed.ID, fixedURL,
 	)
 	assertNoLeakedTarget(t, webhookDB)
 }
@@ -277,15 +277,15 @@ func assertDeliveryUntouched(
 
 // assertReplayTask proves the task handed to the delivery engine is
 // the one the receiver would build for this event and this target, and
-// that it carries wantConfig — the target's configuration as it stands
-// now rather than as the original delivery ran against it.
+// that it carries wantURL — the target's URL as it stands now rather
+// than as the original delivery ran against it.
 func assertReplayTask(
 	t *testing.T,
 	task delivery.Task,
 	webhookID string,
 	event *database.Event,
 	target *database.Target,
-	wantDeliveryID, wantConfig string,
+	wantDeliveryID, wantURL string,
 ) {
 	t.Helper()
 
@@ -295,9 +295,9 @@ func assertReplayTask(
 	assert.Equal(t, event.EntrypointID, task.EntrypointID)
 	assert.Equal(t, target.ID, task.TargetID)
 	assert.Equal(t, target.Type, task.TargetType)
-	assert.JSONEq(
-		t, wantConfig, task.TargetConfig,
-		"replay must use the target's current configuration",
+	assert.Equal(
+		t, wantURL, task.TargetURL,
+		"replay must use the target's current URL",
 	)
 	assert.Equal(t, event.Method, task.Method)
 	assert.Equal(
@@ -349,7 +349,7 @@ func TestHandleDeliveryReplay_RefusesDeletedTarget(t *testing.T) {
 	wh := seedWebhook(t, db)
 	tgt := seedConfiguredTarget(
 		t, db, wh.ID, database.TargetTypeHTTP,
-		`{"url":"`+replayTargetURL+`"}`,
+		database.Target{URL: replayTargetURL},
 	)
 
 	event, original := seedFailedDelivery(
@@ -424,7 +424,7 @@ func TestHandleDeliveryReplay_RefusesWhileEarlierReplayInFlight(
 	wh := seedWebhook(t, db)
 	tgt := seedConfiguredTarget(
 		t, db, wh.ID, database.TargetTypeHTTP,
-		`{"url":"`+replayTargetURL+`"}`,
+		database.Target{URL: replayTargetURL},
 	)
 
 	event, original := seedFailedDelivery(
@@ -498,7 +498,7 @@ func TestHandleDeliveryReplay_ReturnsToTheListItWasPressedIn(
 	wh := seedWebhook(t, db)
 	tgt := seedConfiguredTarget(
 		t, db, wh.ID, database.TargetTypeHTTP,
-		`{"url":"`+replayTargetURL+`"}`,
+		database.Target{URL: replayTargetURL},
 	)
 
 	_, original := seedFailedDelivery(t, dbMgr, wh.ID, tgt.ID)
@@ -556,7 +556,7 @@ func TestHandleSourceLogs_RendersReplayControlAndBanner(t *testing.T) {
 	wh := seedWebhook(t, db)
 	tgt := seedConfiguredTarget(
 		t, db, wh.ID, database.TargetTypeHTTP,
-		`{"url":"`+replayTargetURL+`"}`,
+		database.Target{URL: replayTargetURL},
 	)
 
 	_, original := seedFailedDelivery(t, dbMgr, wh.ID, tgt.ID)
@@ -615,7 +615,7 @@ func TestHandleDeliveryReplay_LabelsTheReplay(t *testing.T) {
 	wh := seedWebhook(t, db)
 	tgt := seedConfiguredTarget(
 		t, db, wh.ID, database.TargetTypeHTTP,
-		`{"url":"`+replayTargetURL+`"}`,
+		database.Target{URL: replayTargetURL},
 	)
 
 	event, original := seedFailedDelivery(t, dbMgr, wh.ID, tgt.ID)