winscope proxy: fix perfetto trace size limit

- Increase perfetto central buffer size to 80'000KB
  (winscope on cloudtop seems to handle up to 100'000).

- Change perfetto config to write the central buffer to disk only once at the end
  of the tracing session. Writing multiple times results in a trace file that grows
  beyond the buffer size.

- Bump proxy version to 2.1.1

Bug: 302645670
Test: capture long SF trace (>30s) and check \
    the perfetto trace file is capped at 80'000KB
Change-Id: Icf3e6200529dd3bd30523f583aaada4c04aca920
2 files changed