fix(5.19): corectii UX/retentie held (findings #2-#6 /code-review high)

#2 Filtrul "doar tinute" (held=1) devine persistent: hidden #f-held in
   #filtre-trimiteri sincronizat prin OOB din _submissions.html + paginare
   pastreaza held=1; chip "Doar tinute manual / Arata tot" ca off-switch.
   Param `held` schimbat la str (held= gol nu mai da 422 la coercion).
#3 Banner bulk "Trimite toate (N)" extras in _bulk_held_banner.html si
   re-randat prin OOB (#bulk-held-banner-wrap) la fiecare reincarcare a listei
   -> nu mai ramane stale dupa eliberari (count revine la 0).
#4 tools/carantina_held seteaza purge_after (blocked_retention_days) pe randurile
   carantinate -> PII nu mai sta la nesfarsit (purge_expired le poate sterge).
#5 Panoul de detaliu marcheaza randul tinut (eticheta amber) si ofera buton
   "Trimite acum la RAR" (paritate cu randul din lista).
#6 expire_held seteaza purge_after=now-1s -> randul expirat e purjabil in ACELASI
   ciclu (purge_expired foloseste comparatie stricta), nu la ciclul urmator.

Teste noi: stickiness held + banner OOB + detaliu buton (test_web_auto_send),
purge_after carantina, purge acelasi-ciclu (test_worker_held). 1541 passed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/web/templates/_submissions.html

@@ -5,6 +5,13 @@
 #}
 <input type="hidden" id="f-page" name="page" value="{{ page | default(1) }}" hx-swap-oob="true">
 
+{# OOB: sincronizeaza filtrul "doar tinute" (#f-held) cu starea randata acum, ca reincarcarile
+   (trimiteriChanged / paginare) sa-l pastreze in loc sa revina la lista completa (/code-review #2). #}
+<input type="hidden" id="f-held" name="held" value="{{ f_held | default('') }}" hx-swap-oob="true">
+
+{# OOB: banner bulk "Trimite toate (N)" re-randat la fiecare reincarcare a listei (fix staleness). #}
+{% with banner_oob = true %}{% include '_bulk_held_banner.html' %}{% endwith %}
+
 {# OOB: re-randeaza pill-urile de stare (in bara de filtre, in afara #submissions-wrap) cu
    contoarele si starea activa proaspete la fiecare reincarcare a tabelului. #}
 <span hx-swap-oob="innerHTML:#pills-categorii">{% include '_pills.html' %}</span>
@@ -22,6 +29,23 @@
 </div>
 {% endif %}
 
+{# US-007 (5.19): chip filtru activ "doar tinute" cu buton de golire (fix /code-review #2 —
+   filtrul held e sticky prin OOB, deci ii dam un off-switch explicit). #}
+{% if f_held %}
+<div style="display:flex; align-items:center; gap:8px; margin-bottom:8px; font-size:var(--fs-sm);">
+  <span style="display:inline-flex; align-items:center; gap:6px; padding:2px 10px; border-radius:99px;
+               border:1px solid var(--warn); color:var(--warn); font-weight:600;">
+    Doar tinute manual
+  </span>
+  <button type="button"
+          onclick="var h=document.getElementById('f-held'); if(h){h.value='';} var f=document.getElementById('filtre-trimiteri'); if(f&&window.htmx){htmx.trigger(f,'submit');}"
+          style="background:none; border:none; color:var(--muted); cursor:pointer;
+                 text-decoration:underline; font-size:var(--fs-sm);">
+    Arata tot
+  </button>
+</div>
+{% endif %}
+
 {% if rows %}
 {# Form bulk cu DOUA actiuni: (1) aplica cod RAR la selectate (bulk-fix, US-010),
    (2) sterge selectate (sterge-bulk). Selectia opereaza DOAR pe randuri blocate
@@ -196,6 +220,7 @@
 {% if f_vehicul %}{% set pq = pq + "&vehicul=" + f_vehicul %}{% endif %}
 {% if f_data_de %}{% set pq = pq + "&data_de=" + f_data_de %}{% endif %}
 {% if f_data_pana %}{% set pq = pq + "&data_pana=" + f_data_pana %}{% endif %}
+{% if f_held %}{% set pq = pq + "&held=" + f_held %}{% endif %}
 
 <nav aria-label="Paginare trimiteri"
      style="display:flex; justify-content:center; gap:4px; flex-wrap:wrap; margin-top:10px;">