[tasks] persist filter state on back navigation

frontend/src/lib/pages/dashboard-personal.svelte

@@ -9,9 +9,12 @@
   import * as Card from "$lib/components/ui/card";
   import type { Task, Project } from "$lib/types/api";
   import { ACTIVE_STATUSES } from "$lib/types/api";
+  import { getSnapshot, saveSnapshot } from "$lib/stores/task-filters.svelte";
 
   let { params = {} }: { params?: Record<string, string> } = $props();
 
+  const ROUTE_KEY = "/dashboard";
+
   let createdTasks = $state<Task[]>([]);
   let assignedTasks = $state<Task[]>([]);
   let projects = $state<Project[]>([]);
@@ -25,6 +28,14 @@
   let searchQuery = $state("");
   let sort = $state("-created_at");
 
+  let saved = getSnapshot(ROUTE_KEY);
+  if (saved) {
+    filterProject = saved.filterProject ?? "";
+    filterStatuses = saved.filterStatuses;
+    filterPriorities = saved.filterPriorities;
+    sort = saved.sort;
+  }
+
   function toggleStatus(s: string) {
     if (filterStatuses.includes(s)) {
       filterStatuses = filterStatuses.filter((x) => x !== s);
@@ -60,6 +71,16 @@
     navigate(`/tasks/${task.id}`);
   }
 
+  $effect(() => {
+    saveSnapshot(ROUTE_KEY, {
+      filterProject: filterProject || undefined,
+      filterStatuses: [...filterStatuses],
+      filterPriorities: [...filterPriorities],
+      sort,
+      offset: 0,
+    });
+  });
+
   $effect(() => {
     loading = true;
     error = "";

frontend/src/lib/pages/dashboard-tasks.svelte

@@ -11,9 +11,12 @@
   import { Button } from "$lib/components/ui/button";
   import type { Project, Task } from "$lib/types/api";
   import { ACTIVE_STATUSES } from "$lib/types/api";
+  import { getSnapshot, saveSnapshot } from "$lib/stores/task-filters.svelte";
 
   let { params = {} }: { params?: Record<string, string> } = $props();
 
+  const ROUTE_KEY = "/dashboard/all";
+
   let tasks = $state<Task[]>([]);
   let total = $state(0);
   let projects = $state<Project[]>([]);
@@ -28,6 +31,15 @@
   let offset = $state(0);
   const limit = 50;
 
+  let saved = getSnapshot(ROUTE_KEY);
+  if (saved) {
+    filterProject = saved.filterProject ?? "";
+    filterStatuses = saved.filterStatuses;
+    filterPriorities = saved.filterPriorities;
+    sort = saved.sort;
+    offset = saved.offset;
+  }
+
   function toggleStatus(s: string) {
     if (filterStatuses.includes(s)) {
       filterStatuses = filterStatuses.filter((x) => x !== s);
@@ -98,6 +110,16 @@
 
   $effect(load);
 
+  $effect(() => {
+    saveSnapshot(ROUTE_KEY, {
+      filterProject: filterProject || undefined,
+      filterStatuses: [...filterStatuses],
+      filterPriorities: [...filterPriorities],
+      sort,
+      offset,
+    });
+  });
+
   function handleTaskClick(task: Task) {
     navigate(`/tasks/${task.id}`);
   }

frontend/src/lib/pages/project-tasks.svelte

@@ -12,17 +12,20 @@
   import { Button } from "$lib/components/ui/button";
   import type { Project, Task } from "$lib/types/api";
   import { ACTIVE_STATUSES } from "$lib/types/api";
+  import { getSnapshot, saveSnapshot } from "$lib/stores/task-filters.svelte";
 
   // svelte-ignore a11y_click_events_have_key_events
 
   let { params = {} }: { params?: Record<string, string> } = $props();
   let slug = $derived(params.slug || "");
+  let routeKey = $derived(`/projects/${slug}`);
 
   let project = $state<Project | null>(null);
   let tasks = $state<Task[]>([]);
   let total = $state(0);
   let loading = $state(true);
   let error = $state("");
+  let currentRouteKey = $state("");
   let sort = $state("-created_at");
   let offset = $state(0);
   const limit = 50;
@@ -31,6 +34,19 @@
   let filterPriorities = $state<string[]>([]);
   let searchQuery = $state("");
 
+  $effect(() => {
+    const saved = getSnapshot(routeKey);
+    if (saved) {
+      filterStatuses = saved.filterStatuses;
+      filterPriorities = saved.filterPriorities;
+      sort = saved.sort;
+      offset = saved.offset;
+    } else {
+      searchQuery = "";
+      sort = "-created_at";
+    }
+  });
+
   function toggleStatus(s: string) {
     if (filterStatuses.includes(s)) {
       filterStatuses = filterStatuses.filter((x) => x !== s);
@@ -78,12 +94,23 @@
         error = e.message || "Failed to load data";
       })
       .finally(() => {
+        currentRouteKey = routeKey;
         loading = false;
       });
   }
 
   $effect(load);
 
+  $effect(() => {
+    if (routeKey !== currentRouteKey) return;
+    saveSnapshot(routeKey, {
+      filterStatuses: [...filterStatuses],
+      filterPriorities: [...filterPriorities],
+      sort,
+      offset,
+    });
+  });
+
   function handleSort(field: string) {
     sort = sort === field ? `-${field}` : field;
     offset = 0;

frontend/src/lib/stores/task-filters.svelte.ts

@@ -0,0 +1,21 @@
+export type FilterSnapshot = {
+  filterProject?: string
+  filterStatuses: string[]
+  filterPriorities: string[]
+  sort: string
+  offset: number
+}
+
+let store = $state<Record<string, FilterSnapshot>>({})
+
+export function getSnapshot(path: string): FilterSnapshot | null {
+  return store[path] ?? null
+}
+
+export function saveSnapshot(path: string, snapshot: FilterSnapshot): void {
+  store[path] = snapshot
+}
+
+export function clearSnapshot(path: string): void {
+  delete store[path]
+}