Say what each action did in a one-line notice (closes #383)

Every action on the webhook pages, and signing out, redirects with a
fixed notice code in the URL, and the page it lands on shows one line
saying what was done. noticeFor maps codes to fixed text and an
unknown code shows nothing, so nothing from the URL is echoed. One
partial, templates/notice.html, shows the line under the navbar on
every page; the error page shows none.

Replay and resubmit use the same codes and partial in place of their
own query parameters and event log banners.

Model: opus-5-5

internal/handlers/source_management.go

@@ -322,7 +322,8 @@ func (h *Handlers) createWebhookWithEntrypoint(
 	)
 
 	http.Redirect(
-		w, r, "/hook/"+webhook.ID, http.StatusSeeOther,
+		w, r, withNotice("/hook/"+webhook.ID, webhookCreated),
+		http.StatusSeeOther,
 	)
 }
 
@@ -579,7 +580,8 @@ func (h *Handlers) applyWebhookEdit(
 	}
 
 	http.Redirect(
-		w, r, "/hook/"+webhook.ID, http.StatusSeeOther,
+		w, r, withNotice("/hook/"+webhook.ID, webhookSaved),
+		http.StatusSeeOther,
 	)
 }
 
@@ -662,7 +664,9 @@ func (h *Handlers) deleteWebhookResources(
 		return
 	}
 
-	http.Redirect(w, r, "/hooks", http.StatusSeeOther)
+	http.Redirect(
+		w, r, withNotice("/hooks", webhookDeleted), http.StatusSeeOther,
+	)
 }
 
 // commitWebhookDeletion soft-deletes a webhook's entrypoints,
@@ -841,31 +845,16 @@ func (h *Handlers) HandleSourceLogs() http.HandlerFunc {
 			totalPages++
 		}
 
-		// The banner a replay or resubmit POST redirected back
-		// with. The message comes from a fixed set keyed by the
-		// outcome code, never from the query string itself.
-		replayMsg, replayOK := replayOutcome(
-			r.URL.Query().Get(replayOutcomeParam),
-		)
-
-		resubmitMsg, resubmitOK := resubmitOutcome(
-			r.URL.Query().Get(resubmitOutcomeParam),
-		)
-
 		data := map[string]any{
-			tmplKeyWebhook:    &webhook,
-			"Events":          evts,
-			"ReplayMessage":   replayMsg,
-			"ReplayQueued":    replayOK,
-			"ResubmitMessage": resubmitMsg,
-			"ResubmitQueued":  resubmitOK,
-			"Page":            page,
-			"TotalPages":      totalPages,
-			"TotalEvents":     total,
-			"HasPrev":         page > 1,
-			"HasNext":         page < totalPages,
-			"PrevPage":        page - 1,
-			"NextPage":        page + 1,
+			tmplKeyWebhook: &webhook,
+			"Events":       evts,
+			"Page":         page,
+			"TotalPages":   totalPages,
+			"TotalEvents":  total,
+			"HasPrev":      page > 1,
+			"HasNext":      page < totalPages,
+			"PrevPage":     page - 1,
+			"NextPage":     page + 1,
 		}
 
 		h.renderTemplate(w, r, "source_logs.html", data)
@@ -1254,7 +1243,8 @@ func (h *Handlers) HandleEntrypointCreate() http.HandlerFunc {
 		}
 
 		http.Redirect(
-			w, r, "/hook/"+webhook.ID, http.StatusSeeOther,
+			w, r, withNotice("/hook/"+webhook.ID, entrypointAdded),
+			http.StatusSeeOther,
 		)
 	}
 }
@@ -1365,7 +1355,8 @@ func (h *Handlers) processTargetCreate(
 	}
 
 	http.Redirect(
-		w, r, "/hook/"+webhook.ID, http.StatusSeeOther,
+		w, r, withNotice("/hook/"+webhook.ID, targetAdded),
+		http.StatusSeeOther,
 	)
 }
 
@@ -1643,6 +1634,7 @@ func (h *Handlers) HandleEntrypointDelete() http.HandlerFunc {
 		"entrypointID", &database.Entrypoint{},
 		"failed to delete entrypoint",
 		nil,
+		entrypointDeleted,
 	)
 }
 
@@ -1655,18 +1647,21 @@ func (h *Handlers) HandleTargetDelete() http.HandlerFunc {
 		"targetID", &database.Target{},
 		"failed to delete target",
 		h.evictArchiveWriterIfUnused,
+		targetDeleted,
 	)
 }
 
 // deleteChildResource returns a handler that deletes a child
 // resource (entrypoint or target) belonging to a webhook. The
 // optional afterDelete hook runs with the webhook's id once the
-// delete has succeeded, before the redirect.
+// delete has succeeded, before the redirect, which carries done as
+// its notice.
 func (h *Handlers) deleteChildResource(
 	idParam string,
 	model any,
 	errMsg string,
 	afterDelete func(webhookID string),
+	done noticeCode,
 ) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		userID, ok := h.getUserID(r)
@@ -1708,7 +1703,7 @@ func (h *Handlers) deleteChildResource(
 
 		http.Redirect(
 			w, r,
-			"/hook/"+webhook.ID,
+			withNotice("/hook/"+webhook.ID, done),
 			http.StatusSeeOther,
 		)
 	}
@@ -1719,7 +1714,7 @@ func (h *Handlers) deleteChildResource(
 func (h *Handlers) HandleEntrypointToggle() http.HandlerFunc {
 	return h.toggleChildResource(
 		"entrypointID",
-		func(webhookID, childID string) error {
+		func(webhookID, childID string) (bool, error) {
 			var ep database.Entrypoint
 
 			err := h.db.DB().Where(
@@ -1727,14 +1722,15 @@ func (h *Handlers) HandleEntrypointToggle() http.HandlerFunc {
 				childID, webhookID,
 			).First(&ep).Error
 			if err != nil {
-				return err
+				return false, err
 			}
 
 			ep.Active = !ep.Active
 
-			return h.db.DB().Save(&ep).Error
+			return ep.Active, h.db.DB().Save(&ep).Error
 		},
 		"failed to toggle entrypoint",
+		entrypointActivated, entrypointDeactivated,
 	)
 }
 
@@ -1742,7 +1738,7 @@ func (h *Handlers) HandleEntrypointToggle() http.HandlerFunc {
 func (h *Handlers) HandleTargetToggle() http.HandlerFunc {
 	return h.toggleChildResource(
 		"targetID",
-		func(webhookID, childID string) error {
+		func(webhookID, childID string) (bool, error) {
 			var tgt database.Target
 
 			err := h.db.DB().Where(
@@ -1750,23 +1746,27 @@ func (h *Handlers) HandleTargetToggle() http.HandlerFunc {
 				childID, webhookID,
 			).First(&tgt).Error
 			if err != nil {
-				return err
+				return false, err
 			}
 
 			tgt.Active = !tgt.Active
 
-			return h.db.DB().Save(&tgt).Error
+			return tgt.Active, h.db.DB().Save(&tgt).Error
 		},
 		"failed to toggle target",
+		targetActivated, targetDeactivated,
 	)
 }
 
 // toggleChildResource returns a handler that toggles the active
-// state of a child resource belonging to a webhook.
+// state of a child resource belonging to a webhook. toggleFn returns
+// the new state, and the redirect carries activated or deactivated as
+// its notice to match.
 func (h *Handlers) toggleChildResource(
 	idParam string,
-	toggleFn func(webhookID, childID string) error,
+	toggleFn func(webhookID, childID string) (bool, error),
 	errMsg string,
+	activated, deactivated noticeCode,
 ) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		userID, ok := h.getUserID(r)
@@ -1792,16 +1792,21 @@ func (h *Handlers) toggleChildResource(
 			return
 		}
 
-		err = toggleFn(webhook.ID, childID)
+		active, err := toggleFn(webhook.ID, childID)
 		if err != nil {
 			h.serverError(w, r, errMsg, err)
 
 			return
 		}
 
+		done := deactivated
+		if active {
+			done = activated
+		}
+
 		http.Redirect(
 			w, r,
-			"/hook/"+webhook.ID,
+			withNotice("/hook/"+webhook.ID, done),
 			http.StatusSeeOther,
 		)
 	}