feat(sources): форма добавления источника — одно поле Address, авто-название из TG/RSS (address-field-enhancement)

- parse_address(address, crawler) в sources/sources.py: telegram (t.me/name, @name,
  https://t.me/s/name) → slug/channel/url; rss → feed_url/url/slug из домена.
- GET /sources/preview: telegram — название через Telethon get_entity (title),
  rss — через feedparser (feed.title); slug и name возвращаются в JSON.
- _form_source: единое поле address вместо url/channel/feed_url; slug из адреса.
- /sources: direction datalist из DIRECTIONS + уникальные значения из БД,
  свободный ввод остаётся.
- Форма: поле Address + кнопка «Найти» (JS fetch → заполнение slug/name),
  direction datalist динамический.

Также в sources.py входит незакоммиченная ранее веб-CRUD-логика (upsert_source_yaml,
delete_source_yaml, sync_yaml_to_db_and_back и др.) — работала на проде, теперь в git.

web/templates/sources.html

@@ -23,13 +23,13 @@
         <input type="text" name="name" class="form-control form-control-sm" placeholder="My Channel">
       </div>
       <div class="col-auto">
-        <label class="form-label mb-0 small">URL</label>
-        <input type="text" name="url" class="form-control form-control-sm" placeholder="https://t.me/... или RSS">
+        <label class="form-label mb-0 small">Address</label>
+        <input type="text" name="address" class="form-control form-control-sm"
+               placeholder="@handle, t.me/name, https://t.me/name или https://.../rss" id="add_address">
       </div>
       <div class="col-auto">
-        <label class="form-label mb-0 small">channel (telegram)</label>
-        <input type="text" name="channel" class="form-control form-control-sm"
-               placeholder="@handle или t.me/..." id="add_channel">
+        <button type="button" class="btn btn-sm btn-outline-secondary" id="btn_fetch"
+                onclick="fetchSourcePreview()">🔎 Найти</button>
       </div>
       <div class="col-auto">
         <label class="form-label mb-0 small">crawler</label>
@@ -38,16 +38,11 @@
           <option value="rss">rss</option>
         </select>
       </div>
-      <div class="col-auto">
-        <label class="form-label mb-0 small">feed_url (rss)</label>
-        <input type="text" name="feed_url" class="form-control form-control-sm" placeholder="https://.../rss">
-      </div>
       <div class="col-auto">
         <label class="form-label mb-0 small">direction</label>
         <input type="text" name="direction" class="form-control form-control-sm" placeholder="linux" list="dirs">
         <datalist id="dirs">
-          <option value="linux"><option value="tech"><option value="politics">
-          <option value="games"><option value="electronics"><option value="llm">
+          {% for d in directions %}<option value="{{ d }}">{% endfor %}
         </datalist>
       </div>
       <div class="col-auto">
@@ -67,13 +62,31 @@
     </form>
     <script>
       const addCrawler = document.querySelector('form[action="/sources/add"] select[name="crawler"]');
-      const addChannel = document.getElementById('add_channel');
-      if (addCrawler && addChannel) {
-        function toggleChannelRequired() {
-          addChannel.required = addCrawler.value === 'telegram';
+      const addAddress = document.getElementById('add_address');
+      const addSlug = document.querySelector('form[action="/sources/add"] input[name="slug"]');
+      const addName = document.querySelector('form[action="/sources/add"] input[name="name"]');
+
+      if (addCrawler && addAddress) {
+        function toggleAddress() {
+          addAddress.placeholder = addCrawler.value === 'telegram'
+            ? '@handle, t.me/name, https://t.me/name'
+            : 'https://.../rss или http://...';
         }
-        addCrawler.addEventListener('change', toggleChannelRequired);
-        toggleChannelRequired();
+        addCrawler.addEventListener('change', toggleAddress);
+        toggleAddress();
+      }
+
+      async function fetchSourcePreview() {
+        const addr = addAddress.value.trim();
+        if (!addr) { alert('Введите адрес'); return; }
+        try {
+          const resp = await fetch(`/sources/preview?address=${encodeURIComponent(addr)}&crawler=${addCrawler.value}`);
+          const data = await resp.json();
+          if (data.error) { alert(data.error); return; }
+          if (data.slug) addSlug.value = data.slug;
+          if (data.name) { addName.value = data.name; }
+          else if (addName.value === '') addName.placeholder = 'Название не найдено — введите вручную';
+        } catch (e) { alert('Ошибка запроса: ' + e); }
       }
     </script>
   </div>