fix(#4724): classify Surefire/Failsafe XML as RED evidence (#4825)

* test(#4724): add failing-first coverage for Surefire XML RED evidence

* fix(#4724): classify Surefire/Failsafe XML as RED evidence

check tdd-red-evidence parsed only node:test TAP, so a JVM project's
genuine Maven red scored INVALID_RED while hand-written synthetic TAP
scored RED_EVIDENCE_OK — the gate was passable only by fabricating its
input (issue #4724's measured repro).

classifyRedEvidence detects Surefire/Failsafe XML (a <testsuite> element)
and parses it by TAG-BOUNDARY scanning: each <testcase> owns its own tag
(self-closing) or the segment up to its </testcase> closer, so the
issue's warned-about spanning trap (a lazy lazy match from a green
self-closing case to the next closing tag) cannot misreport names. A
<failure> or <error> child marks the case failing; the target matches at
class granularity (exact classname, dotted-suffix, or method name). Any
parse anomaly degrades to not-failing — the module stays fail-closed and
PURE (no fs/clock; report freshness remains the workflow's run-start
check per the issue's implementation notes).

TAP classification is byte-identical: all existing fixtures stay green.

* test(#4724): pin the scanner hardening — truncation, TAP-message flip, CDATA phantom

* docs(#4724): backfill changeset PR number

---------

Co-authored-by: sim <sim@local>

.changeset/bold-deer-click.md

@@ -0,0 +1,5 @@
+---
+type: Fixed
+pr: 4825
+---
+**TDD red evidence accepts Surefire/Failsafe XML** — the tdd-red-evidence gate parsed only node:test TAP, so a JVM project's genuine Maven red scored INVALID_RED while hand-written synthetic TAP scored RED_EVIDENCE_OK (the gate was passable only by fabricating its input). Surefire/Failsafe XML reports now classify by tag-boundary scanning: a testcase with a <failure> or <error> child for the target class is a real red; self-closing passing cases are never spanned into failing names. (#4724)