fix(audit): close two Citation Audit coverage holes

Two regressions surfaced when the Citation Audit GitHub workflow turned
red on the v1.15.6 release commit (run 26375546484, exit 1: "476 ok /
1 mismatch / 1 unresolved").

Root causes — both in tools/audit_citations.py, both pre-existing
(workflow has been red since at least v1.15.5):

1. DOI regex captured markdown autolink closers.
   ``docs/joss_validation_dossier.md:9`` writes the Zenodo concept DOI
   as ``<https://doi.org/10.5281/zenodo.19933900>``. The DOI character
   class ``[^\s()"'\`,;}\]\[]+`` did NOT exclude ``<`` / ``>``, so the
   match captured the trailing ``>``, then Crossref + DataCite both
   404'd on ``10.5281/zenodo.19933900>``. RFC 3986 reserves angle
   brackets in URIs (must be percent-encoded), so adding ``<>`` to the
   exclusion class and to the trailing-boundary lookahead is safe.

2. ``_bibtex_markers`` missed ``@software{`` (and adjacent valid
   BibTeX types ``@unpublished{`` / ``@incollection{``).
   ``src/statspai/_citation.py:26`` defines ``_CONCEPT_DOI``; four
   lines below sits a Python string template ``"@software{{...``
   carrying the canonical author list. The ±3 claim-block window
   captured the template but the marker set didn't recognise
   ``@software{`` as a BibTeX block, so the script ran the missing-
   author check and flagged "missing author(s): Rozelle, Scott".
   Adding the three types to the marker tuple lets the script trust
   the structured ``author={...}`` field for software / unpublished /
   incollection entries the same way it does for ``@article`` etc.

Verification (all four gates, locally, cache cleared):
- Gate 0: 32/32 auditor unit tests pass
- Gate 1: paper.bib has 0 duplicate keys / DOIs / arXiv ids
- Gate 2: 0 dangling refs across src/ docs/ paper.md
- Gate 3: 478 ok / 0 mismatch / 0 unresolved, exit 0

No package source touched — pure tooling fix, no version bump needed.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: brycewang-stanford

tools/audit_citations.py

@@ -92,19 +92,24 @@
 # like ``10.1016/S0169-7218(11)00407-2``, Emerald volume 20 like
 # ``10.1108/S1049-2585(2012)0000020009``). Up to 2 levels of nesting
 # is plenty in practice.
-_DOI_NO_PAREN = r"[^\s()\"'`,;}\]\[]+"
+#
+# ``<`` / ``>`` are excluded so that markdown autolinks of the form
+# ``<https://doi.org/10.xxxx/yyyy>`` don't pull the trailing ``>`` into
+# the DOI body. RFC 3986 reserves angle brackets in URIs (they must be
+# percent-encoded), so no real DOI contains a literal ``<`` or ``>``.
+_DOI_NO_PAREN = r"[^\s()<>\"'`,;}\]\[]+"
 _DOI_PAREN = rf"\(?:{_DOI_NO_PAREN}\)?"  # placeholder, see verbose form
 DOI_RE = re.compile(
     r"""
     \b(?P<id>
         10\.\d{4,9}/                       # DOI prefix
         (?:
-              [^\s()"'`,;}\]\[]            # non-paren body char
-            | \( [^\s()"'`,;}\]\[]* \)     # balanced (...) one level
+              [^\s()<>"'`,;}\]\[]          # non-paren body char
+            | \( [^\s()<>"'`,;}\]\[]* \)   # balanced (...) one level
         )+?
     )
     \.?                                    # optional trailing period
-    (?= [\s)\"'`,;}\]\[] | $ )
+    (?= [\s)<>\"'`,;}\]\[] | $ )
     """,
     re.VERBOSE,
 )
@@ -645,7 +650,8 @@ def diff_citation(c: Citation, truth: PaperMeta) -> list[str]:
         "author={", "title={", "journal={", "booktitle={",
         "year={", "doi={", "volume={", "number={", "pages={",
         "publisher={", "@article{", "@inproceedings{", "@book{",
-        "@misc{", "@techreport{", "@phdthesis{",
+        "@misc{", "@techreport{", "@phdthesis{", "@software{",
+        "@unpublished{", "@incollection{",
     )
     is_bibtex = any(m in c.claim_block for m in _bibtex_markers)