Bridge: report through the plugin logger, not System.out

[CaYatur]

Bridge: report through the plugin logger, not System.out

Paper nags about it, and Paper is right:

Nag author(s): '[CaYaDev]' of 'MSMS-Bridge v1.0.0' about their usage of
System.out/err.print. Please use your plugin's logger instead.

A plugin writing to the raw stream bypasses the log file, the timestamps and
every appender the operator has configured. The transport is unchanged — the
server console is still how this reports, which is why installing it opens no
extra port — and the manager finds the line by its marker, which the logger's
own prefix leaves untouched.

SelfTest keeps its System.out: it is a harness that runs under plain java
and is excluded from the jar, so Paper never loads it.

Also: build.mjs no longer hardcodes the jar's version in its filename. It
reads it from plugin.yml, which is the file that defines it. The app finds the
jar by parsing that filename and the smoke asserts the shipped jar matches what
plugin.yml declares — two places to change is one place to forget, and the
failure is a plugin reporting a version it is not.

Bundled jar rebuilt at 1.0.1.

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[CaYatur]

Self-review: the logger prefix is one rename from breaking the parser

Going through the plugin logger means Paper prints the plugin name in front of
every message. The plugin is MSMS-Bridge; the marker the parser looks for is
[MSMS-BRIDGE]. Those differ only in case, and parseBridgeLine slices at the
FIRST match — so if the two ever became the same string, every message would be
cut at the wrong place and parse as nothing. Silently: no error, just a bridge
that never reports.

Asserted, tied to the two real sources rather than to a literal — the marker
constant and the name in plugin.yml — plus a parse of a genuine
logger-formatted line with the prefix in front of it.