feat: add resolve_object_url helper and notification click-through with comment highlighting

Extract duplicate target-redirect logic from comments router into a new `resolve_object_url` database function, add `target_url` field to follow and message notifications, create `/notifications/open/{uid}` endpoint that marks notifications read and redirects to their target, implement client-side NotificationManager for card clicks and comment hash scrolling, and add comment-highlight CSS animation.

devplacepy/static/css/notifications.css

@@ -31,6 +31,7 @@
     border-radius: var(--radius-lg);
     padding: 1.25rem;
     transition: all 0.2s;
+    cursor: pointer;
 }
 
 .notification-card.unread {

devplacepy/static/css/post.css

@@ -115,6 +115,22 @@
     min-width: 0;
 }
 
+.comment-highlight {
+    animation: comment-highlight-fade 2s ease-out;
+    border-radius: var(--radius);
+}
+
+@keyframes comment-highlight-fade {
+    from {
+        background: var(--accent-light);
+        box-shadow: 0 0 0 4px var(--accent-light);
+    }
+    to {
+        background: transparent;
+        box-shadow: 0 0 0 4px transparent;
+    }
+}
+
 .comment-header {
     display: flex;
     align-items: center;

devplacepy/static/js/Application.js

@@ -1,6 +1,7 @@
 import { ModalManager } from "./ModalManager.js";
 import { FormManager } from "./FormManager.js";
 import { VoteManager } from "./VoteManager.js";
+import { NotificationManager } from "./NotificationManager.js";
 import { MessageSearch } from "./MessageSearch.js";
 import { ProfileEditor } from "./ProfileEditor.js";
 import { MobileNav } from "./MobileNav.js";
@@ -15,6 +16,7 @@ class Application {
         this.modals = new ModalManager();
         this.forms = new FormManager();
         this.votes = new VoteManager();
+        this.notifications = new NotificationManager();
         this.messageSearch = new MessageSearch();
         this.profile = new ProfileEditor();
         this.mobileNav = new MobileNav();

devplacepy/static/js/NotificationManager.js

@@ -0,0 +1,51 @@
+import { Http } from "./Http.js";
+
+export class NotificationManager {
+    constructor() {
+        this.initCardNavigation();
+        this.initDismiss();
+        this.initHashScroll();
+    }
+
+    initCardNavigation() {
+        document.querySelectorAll(".notification-card[data-href]").forEach((card) => {
+            card.addEventListener("click", (e) => {
+                if (e.target.closest("a, button")) {
+                    return;
+                }
+                window.location.href = card.dataset.href;
+            });
+        });
+    }
+
+    initDismiss() {
+        document.querySelectorAll(".notification-dismiss").forEach((btn) => {
+            btn.addEventListener("click", (e) => {
+                e.preventDefault();
+                const uid = btn.dataset.uid;
+                if (!uid) {
+                    return;
+                }
+                Http.postForm(`/notifications/mark-read/${uid}`);
+            });
+        });
+    }
+
+    initHashScroll() {
+        const hash = window.location.hash;
+        if (!hash.startsWith("#comment-")) {
+            return;
+        }
+        window.addEventListener("load", () => {
+            const target = document.getElementById(hash.slice(1));
+            if (!target) {
+                return;
+            }
+            requestAnimationFrame(() => {
+                target.scrollIntoView({ behavior: "smooth", block: "center" });
+                target.classList.add("comment-highlight");
+                setTimeout(() => target.classList.remove("comment-highlight"), 2000);
+            });
+        });
+    }
+}

devplacepy/static/js/VoteManager.js

@@ -3,7 +3,6 @@ import { Http } from "./Http.js";
 export class VoteManager {
     constructor() {
         this.initVoteButtons();
-        this.initNotificationDismiss();
     }
 
     initVoteButtons() {
@@ -15,16 +14,4 @@ export class VoteManager {
             });
         });
     }
-
-    initNotificationDismiss() {
-        document.querySelectorAll(".notification-dismiss").forEach((btn) => {
-            btn.addEventListener("click", () => {
-                const uid = btn.dataset.uid;
-                if (!uid) {
-                    return;
-                }
-                Http.postForm(`/notifications/mark-read/${uid}`);
-            });
-        });
-    }
 }