[Update]: Moved strings to strings.asm

[douxxtech]

This PR moves user-faceing strings, previously located into logutils.asm, into a new strings.asm file.
Additionally, some minor cleanup has also been done into sysutils.asm

[github-actions]

START + GET /: 166 syscalls
Fastest: 0.000015s (lseek)
Slowest: 0.708286s (accept)

threads: 4 (auto), conns: 50, duration: 20s

[wrk]
Running 20s test @ http://127.0.0.1:8080/
  4 threads and 50 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency     5.07ms   10.64ms 419.55ms   99.39%
    Req/Sec     1.68k   358.38     2.51k    68.75%
  133809 requests in 20.05s, 203.03MB read
  Socket errors: connect 0, read 730, write 0, timeout 0
Requests/sec:   6673.19
Transfer/sec:     10.13MB