feat: CAP memory estimation with a confirm step before install (v3.5.8)

Selecting a .cap in the RAM installer or the SCP81 "Install from .cap"
template now runs a read-only analysis (POST /api/cap-info) before any
APDU is built: the archive is validated structurally (a corrupt or
wrong-format file fails here) and the bundled capmem analyzer estimates
the code size and the persistent (NVRAM) / volatile (RAM) requirements,
with the tool's suggested C6/C7/C8 quotas shown as information.  The
form's action button (Execute / Generate) stays disabled until the
analysis succeeds - pressing it is the user's confirmation to continue.

- pysim_simple_server/capmem.py: bundled analyzer (component parsers +
  JCVM opcode table + method-bytecode allocation scan), adapted to take
  the CAP archive as bytes and return report/memory dicts; output
  verified byte-identical to the workspace tool on 21 real CAPs.
- _cap_info_body + POST /api/cap-info (read-only; the install endpoints
  stay unchanged and self-sufficient).
- PWA: shared capAnalyzeFile/capMemHtml/capGateOk helpers, estimate box
  under both CAP inputs (reusing the idle #ram-cap-info div, new
  #scripts-cap-info), data-cap-gate gating in pysimApplyAvailability,
  stale-response guard, Retry, EN/RU strings.
- Tests: tests/test_cap_memory.py (synthetic CAPs: new/newarray/
  makeTransientByteArray/static fields/unknown-opcode warnings/corrupt
  input), frontend capmem.test.js (renderer, gate, analyze flow).
- help EN/RU, docs/api.md, AGENTS; version 3.5.8; sw cache simple-v261.

567 frontend / 429 Python green.

frontend/sw.js

@@ -1,4 +1,4 @@
-const CACHE = 'simple-v260';
+const CACHE = 'simple-v261';
 const URLS = [
   'index.html',
   'help.html',