Packets longer than one SMS now go out as concatenated SMS-PP downloads
per TS 31.115 4.3 and the UI shows how many SMS a packet needs.
Server:
- `_split_secured_packet` cuts the command packet at the exact SMS
user-data capacities (first SM 132 octets: concat IE 5 + CPI IE 2;
following ones 134; a single-SM packet may be 137 with the CPI IE) and
`_build_sms_tpdu` tags every segment with the fixed concatenation
reference 01; `_build_sms_tpdu` also enforces the 140-octet budget.
- `_send_secured_packet` (shared by /api/send-ota and /api/ram-install)
sends one ENVELOPE per segment in order, refuses more than
MAX_ENVELOPE_SEGMENTS (5, the card's concatenation buffer) and reports
`bytes`/`segments` in the response (RAM install per step as well).
- `_build_secured_packet`/`_encode_cmd_unlimited`: our own TS 102 225
5.1.1 encoder on pySim's keyset/header constructors, byte-identical to
pySim for packets <= 140 octets (tests) and not limited to one SMS
(pySim refuses the longer ones, which is why they never went out).
- RAM LOAD blocks are no longer clamped to one SMS: 1-240 bytes of
payload with the default 240 (the GP maximum); `load_block_size_auto`
replaces `load_block_size_clamped`.
PWA:
- `scp80SegmentInfo` / `spSizeInfoText` show "N bytes . M SMS
(concatenated)" under the packet field, turn red past 5 SMS and report
size/SMS in the send result and the RAM step log; LOAD block hints and
placeholders updated; EN/RU.
Tests/docs: Python +2 cases incl. segment order/capacities and byte
identity with pySim; Node drift guard against the server constants and
UI text tests; README/README_RUS, help EN/RU, docs/api.md, AGENTS.