Use non-autoflush PrintStream rather than LogStream for mall prices.

[phulin]

I meant to include this in #1382 - the price writing code should use a buffered output stream, instead of a LogStream which auto-flushes each byte array write.

This PR reduces time on the below benchmark from about 10 s to about 500 ms.

  @Test
  void speed() {
    int N = 300;
    MallPriceDatabase.savePricesToFile = true;
    for (var entry : ItemDatabase.entrySet()) {
      MallPriceDatabase.recordPrice(entry.getKey(), entry.getKey(), true);
    }
    for (int i = 0; i < 2 * N / 5; i++) {
      MallPriceDatabase.writePrices();
    }
    long start =
        ManagementFactory.getThreadMXBean().getThreadCpuTime(Thread.currentThread().getId());
    for (int i = 0; i < N; i++) {
      MallPriceDatabase.writePrices();
    }
    long end = ManagementFactory.getThreadMXBean().getThreadCpuTime(Thread.currentThread().getId());
    System.out.println("Elapsed: " + (end - start) / 1_000_000);
    new File(KoLConstants.DATA_LOCATION, "mallprices.txt").delete();
  }

[codecov]

Codecov Report

Merging #1388 (91b90e9) into main (d24fa65) will decrease coverage by 0.00%.
The diff coverage is 0.00%.

❗ Current head 91b90e9 differs from pull request most recent head a2eb298. Consider uploading reports for the commit a2eb298 to get more accurate results

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #1388      +/-   ##
============================================
- Coverage     33.56%   33.55%   -0.01%     
+ Complexity    16747    16746       -1     
============================================
  Files          1049     1049              
  Lines        162125   162128       +3     
  Branches      34849    34850       +1     
============================================
- Hits          54412    54408       -4     
- Misses        98381    98387       +6     
- Partials       9332     9333       +1     

Impacted Files	Coverage Δ
...eforge/kolmafia/persistence/MallPriceDatabase.java	41.61% <0.00%> (-0.29%)	⬇️
.../sourceforge/kolmafia/request/StandardRequest.java	81.08% <0.00%> (-2.71%)	⬇️
src/net/sourceforge/kolmafia/RequestThread.java	36.96% <0.00%> (-1.22%)	⬇️
...ourceforge/kolmafia/textui/command/BuyCommand.java	7.50% <0.00%> (-0.40%)	⬇️

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[midgleyc]

Confirmation: does the writer flush automatically before being closed?

This is probably a problem in many places in the codebase; could it be centralised somewhere? Doesn't have to be done as part of this PR. I think we have many classes that deal with reading from / writing to files already.

[phulin]

It does flush before writing, see PrintStream.close documentation:

[phulin]

And yeah, it should be done elsewhere. DataUtilities.getOutputStream should probably return a buffered output stream by default...