Fix status filter: strict tree filtering and URL param handling

- render_tree_node now applies entry_matches_filter directly; parent
  entries no longer bleed through when only a descendant matches
- Filter dropdowns use set_filter() to persist state in URL query params
- apply_search() reads filter state from URL on init and popstate
- build_url() encodes filter state; uses ?status=all for "all statuses"
  to distinguish from absent param (which defaults to open)
- apply_search() treats absent or empty status param as 'open'

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

public/app.mjs

@@ -306,8 +306,8 @@ function make_entry_row(entry, children_map) {
 	return row;
 }
 
-function render_tree_node(entry, children_map, is_child = false) {
-	if (!is_child && !node_or_descendants_match(entry, children_map)) { return null; }
+function render_tree_node(entry, children_map) {
+	if (!entry_matches_filter(entry)) { return null; }
 
 	const children = children_map.get(entry.id) ?? [];
 	const node = document.createElement('div');
@@ -318,7 +318,8 @@ function render_tree_node(entry, children_map, is_child = false) {
 		const children_el = document.createElement('div');
 		children_el.className = 'task-children';
 		for (const child of children) {
-			children_el.appendChild(render_tree_node(child, children_map, true));
+			const child_node = render_tree_node(child, children_map);
+			if (child_node) { children_el.appendChild(child_node); }
 		}
 		node.appendChild(children_el);
 	}
@@ -409,7 +410,7 @@ function render_entries(container) {
 		if (val === state.filter_status) { opt.selected = true; }
 		status_sel.appendChild(opt);
 	}
-	status_sel.addEventListener('change', () => { state.filter_status = status_sel.value; render(); });
+	status_sel.addEventListener('change', () => { set_filter('filter_status', status_sel.value); });
 	filter_bar.appendChild(status_sel);
 
 	const priority_sel = document.createElement('select');
@@ -419,7 +420,7 @@ function render_entries(container) {
 		if (val === state.filter_priority) { opt.selected = true; }
 		priority_sel.appendChild(opt);
 	}
-	priority_sel.addEventListener('change', () => { state.filter_priority = priority_sel.value; render(); });
+	priority_sel.addEventListener('change', () => { set_filter('filter_priority', priority_sel.value); });
 	filter_bar.appendChild(priority_sel);
 
 	const tag_sel = document.createElement('select');
@@ -443,7 +444,7 @@ function render_entries(container) {
 	search_input.type = 'text';
 	search_input.placeholder = 'Search…';
 	search_input.value = state.search;
-	search_input.addEventListener('input', () => { state.search = search_input.value; render(); });
+	search_input.addEventListener('input', () => { set_filter('search', search_input.value); });
 	filter_bar.appendChild(search_input);
 
 	container.appendChild(filter_bar);
@@ -464,7 +465,7 @@ function render_entries(container) {
 			list.appendChild(make_entry_row(entry, children_map));
 		}
 	} else {
-		const visible = roots.filter(e => node_or_descendants_match(e, children_map));
+		const visible = roots.filter(e => entry_matches_filter(e));
 		if (!visible.length) {
 			const empty = document.createElement('div');
 			empty.className = 'empty-state';
@@ -646,14 +647,38 @@ function navigate_new(type, parent_id) {
 	navigate(hash);
 }
 
+function build_url(hash) {
+	const params = new URLSearchParams();
+	if (state.filter_status !== 'open') { params.set('status', state.filter_status || 'all'); }
+	if (state.filter_priority)          { params.set('priority', state.filter_priority); }
+	if (state.search)                   { params.set('search', state.search); }
+	const qs = params.toString();
+	return (qs ? '?' + qs : '') + '#' + hash;
+}
+
+function apply_search() {
+	const params = new URLSearchParams(location.search);
+	const s = params.get('status');
+	state.filter_status   = (s === null || s === '') ? 'open' : (s === 'all' ? '' : s);
+	state.filter_priority = params.get('priority') ?? '';
+	state.search          = params.get('search')   ?? '';
+}
+
 function navigate(hash) {
-	history.pushState(null, '', '#' + hash);
+	history.pushState(null, '', build_url(hash));
 	apply_hash(hash);
 	render();
 }
 
+function set_filter(key, val) {
+	state[key] = val;
+	history.replaceState(null, '', build_url(location.hash.slice(1)));
+	render();
+}
+
 window.addEventListener('popstate', () => {
 	apply_hash(location.hash.slice(1));
+	apply_search();
 	render();
 });
 
@@ -1188,6 +1213,7 @@ async function init() {
 	state.entry_types = types_res.entry_types;
 	state.entries     = entries_res.entries;
 
+	apply_search();
 	apply_hash(location.hash.slice(1));
 	render();
 }