feat: polling on by default and an effective-state toggle (v3.5.10)

- Background STATUS polling is enabled by default, per the spec's idle
  polling rule (TS 102 221 14.6.2): `_POLL_ENABLED = True`, __main__ runs
  `_poll_enable()` regardless of card presence (--poll-interval 0 still
  disables) and `_do_status_poll` keeps ticking while enabled even without
  a session, so a cardless start resumes as soon as a card appears.
- A new card session clears a POLLING OFF from the previous card in
  `_apply_equipped_card` before re-enabling polling.
- The Phone-tab toggle now shows the *effective* state: OFF in amber
  ("card disabled polling (POLLING OFF)") while the card suspended
  proactive polling, back to ON on the next POLL INTERVAL.  The 5 s
  background poll now passes `card_disabled` through (it was dropped, so
  an autonomously received POLLING OFF never reached the UI).
- Tests: poll_ui updated (button OFF while suspended, warning path),
  test_poll +2 (cardless ticking, module default via a subprocess check).
- Help EN/RU, docs/api.md, AGENTS; version 3.5.10; sw cache simple-v263.

573 frontend / 441 Python green.

frontend/help.html

@@ -503,7 +503,7 @@
 	<p class="text-sm mb-3">The <strong>TERMINAL PROFILE</strong> block (next to STATUS and Polling) offers <strong>Send</strong> (re-sends it, like Rescue) and <strong>Configure</strong>. The Configure dialog has a preset selector (device models, e.g. this project's BIP-capable handset profile), a hex field and a form with one checkbox per profile bit decoded per <strong>TS 102 223 &sect;5.2</strong> / <strong>TS 31.111 &sect;5.2</strong> (bytes 1&ndash;39, 3GPP-defined bits use the TS 31.111 names), each byte is a vertical list of its bits in spec order (<strong>b1 is the least significant bit and the first table row</strong>); bits that form a numeric value field per the spec (byte 11 soft keys, byte 13 BIP channels, byte 14/15 screen height/width, byte 16 menu width reduction, byte 19 TIA/EIA-136 version, byte 24 max frames) are shown as a single number input for the whole bit range, with the byte 11 <code class="font-mono text-sm">'FF'</code> reserved value noted in the hint; placed in fixed column groups (bytes 1-12 in 2 columns, 13-16 in 4, 17-18 in 2, 19-21 in 3, 22-25 in 2, 26-28 in 3, 29-30 in 2, later bytes one per row); toggling a bit updates the hex and editing the hex re-renders the form &mdash; the hex field is authoritative and unknown bytes/bits are preserved. <strong>Apply</strong> sends the new value to the server (and on to the card), resetting the STK session like Rescue; the change is in-memory only (the <code class="font-mono text-sm">--terminal-profile</code> CLI value is the startup default). The rules for inferring device characteristics from a TP (radio generation, headless modems, standards family) are collected in <code class="font-mono text-sm">docs/TERMINAL_PROFILE.md</code>.</p>
 
 	<h3 id="status-polling" class="text-lg font-medium mb-2">8.5 STATUS polling</h3>
-	<p class="text-sm mb-3">A <strong>Send STATUS</strong> button issues a manual STATUS (F2). A <strong>Polling</strong> toggle enables background polling: after a configurable idle interval (server CLI <code class="font-mono text-sm">--poll-interval</code>, 1&ndash;255&nbsp;s, default 30&nbsp;s, <code class="font-mono text-sm">0</code> disables polling) the server sends STATUS and handles any pending proactive command. The card's <strong>POLL INTERVAL</strong> command updates the interval (TS 102 223 &sect;6.4.6; the TERMINAL RESPONSE reports the interval actually used), and a <strong>POLLING OFF</strong> suspends polling until a new POLL INTERVAL &mdash; the panel shows that state in amber while the manual <strong>Send STATUS</strong> button keeps working (presence detection and manual STATUS are not affected by POLLING OFF). Polling stops and card state resets if the card is removed.</p>
+	<p class="text-sm mb-3">A <strong>Send STATUS</strong> button issues a manual STATUS (F2). Background <strong>Polling</strong> is on by default (a CAT terminal polls during idle, TS 102 221 &sect;14.6.2): after the idle interval (server CLI <code class="font-mono text-sm">--poll-interval</code>, 1&ndash;255&nbsp;s, default 30&nbsp;s, <code class="font-mono text-sm">0</code> disables polling) the server sends STATUS and handles any pending proactive command. The toggle turns it off/on; the card's <strong>POLL INTERVAL</strong> command updates the interval (TS 102 223 &sect;6.4.6; the TERMINAL RESPONSE reports the interval actually used), and after a <strong>POLLING OFF</strong> the toggle shows <strong>OFF</strong> in amber until a new POLL INTERVAL arrives &mdash; the manual <strong>Send STATUS</strong> button keeps working (presence detection and manual STATUS are not affected by POLLING OFF). Polling is disabled when the card is removed and re-enabled by the next equip.</p>
 
 	<h3 id="pli-dict" class="text-lg font-medium mb-2">8.6 TR Config &mdash; PROVIDE LOCAL INFORMATION response data</h3>
 	<p class="text-sm mb-2">Editable hex values for all 22 PLI qualifiers (TS 102 223 &sect;8.6 + TS 131 111). Ten qualifiers have inline decode/encode forms:</p>