Update trace buffer to support SysUI & Launcher

- Move TraceBuffer to sysui-accessible package, and make it generic
  to support both lite and nano proto callers
- Expose shell command to start/stop sysui tracing

Bug: 144854916
Test: atest TraceBufferTest

Change-Id: Id117024d943f148a91631fd9fcae1fd70fca8ab5