Adds three COORDS_*_REGEX constants (at-clause, bracketed, parenthesised)
plus COORDS_REPLACEMENT, wires them into redact(), and covers all three
contexts with 8 new tests including a critical negative test asserting
DebugLog-server.txt server-metadata triples are not redacted.
Also updates two Task 3 player-name tests whose expected strings now
include the coords redaction that the wired pass applies.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>