fix: use the card's own SimCardCommands for ADM and AUTHENTICATE (v2.7.20)

/api/verify-adm sent VERIFY with CLA A0 on a UICC (SW 6E00) while
pySim-shell's verify_adm worked: fast init builds the card on its own
SimCardCommands instance, but __main__ kept server.scc at the startup
placeholder left at the SIM defaults; only an equip repointed it.

- __main__ adopts card._scc after init (cat_cla still set on it), so
  server.scc carries the card's cla_byte/sel_ctrl from startup on.
- _verify_adm prefers app.rs.lchan[0].scc / app.card._scc, exactly like
  pySim-shell's verify_adm, independent of server.scc.
- netsim AUTHENTICATE follows the card class: a UICC gets 00 88 00 81 22
  (RAND+AUTN, DB/DC response), a SIM gets A0 88 00 00 10 (RAND only,
  SRES+Kc); the 61xx GET RESPONSE uses the same CLA.
- tests: ADM with a stale placeholder scc; 2G builder/parser; SIM-CLA
  runner case; help EN/RU and AGENTS updated.

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "pysim-simple-server"
-version = "2.7.19"
+version = "2.7.20"
 description = "HTTP REST server wrapping pysim for the SIMple PWA"
 requires-python = ">=3.8"
 # pysim is a git-only dependency installed explicitly by setup.bat/setup.sh.