Fix every real lint finding and drop degenerate splice fragments

CLAUDE.md

@@ -31,6 +31,16 @@ See `docs/pdf-parsing-outlier-catalog.md` and
 `docs/adr/0003-pdf-parsing-strategy.md` for the concrete track record this
 rule comes from.
 
+**What "verified" means:** when reporting something as verified, state (1)
+the command/test/script/manual check that was run, (2) the exact input
+scope, (3) the expected invariant or acceptance condition, (4) the observed
+result, and (5) any part of the requested scope that was *not* covered.
+Distinct scopes (unit test, regression fixture, selected-page sample,
+selected monographs, all detected monographs, full 1668-page document) are
+not interchangeable — don't describe one as another. Avoid words like
+"fully verified", "complete", "all", "no data lost", or "production-ready"
+unless the checks actually performed support that literal claim.
+
 ## Real code follows Clean Code / Clean Architecture / SoC / DRY / SOLID
 
 Applies to anything meant to be committed as part of the actual system
@@ -70,3 +80,62 @@ checklist is what actually catches that, the same reasoning behind the
   where the *why* isn't obvious from the code itself) — matches the
   no-comments-unless-non-obvious style already used throughout this
   project's docs and ADRs.
+
+## Preserve provenance
+
+Every extracted or transformed unit must retain enough provenance to trace
+it back to the source document — depending on the data type, this may
+include document id, page number, source block/span id, bounding box,
+reading-order position, table id and row/column coordinates, formula
+source span, monograph id, section path, and extraction method/parser
+version.
+
+**Why:** this is a medical reference book being turned into a chatbot's
+knowledge base — if an answer is wrong, being able to trace a chunk back to
+the exact page/span it came from is how it gets debugged and corrected.
+Normalized text that "looks right" is not the same guarantee as text that
+is traceable.
+
+**How to apply:**
+- Don't discard provenance fields just because the normalized text appears
+  correct — a text value that can't be traced back to its source is not a
+  fully validated extraction result.
+- When adding a new pipeline stage or record type, carry existing
+  provenance fields through rather than dropping them at the boundary.
+
+## Investigation scripts are evidence tools, not production code
+
+One-off investigation scripts (e.g. scanning the corpus to check a
+hypothesis) may optimize for speed, but they must:
+- be clearly named or located as temporary investigation code;
+- state or record the scope they scanned;
+- output enough information to reproduce or inspect the finding;
+- not be imported by production code, and not become the only
+  implementation of a parsing rule;
+- not be cited as whole-document evidence unless they actually covered the
+  whole document;
+- be deleted after their finding is captured in a regression test, fixture,
+  ADR, or the outlier catalog.
+
+When an investigation uncovers a real parsing rule, move that rule into the
+production implementation and validate both the production code and the
+regression fixture — per [[DRY]] above, the rule should end up living in
+exactly one place.
+
+## Definition of done
+
+A task is not complete merely because code was written. Before reporting
+completion:
+- run the most relevant available tests and validation commands, and
+  report the exact commands/checks run and whether each passed or failed;
+- state the validation scope (see "What 'verified' means" above);
+- add or update a regression fixture for each parser bug fixed;
+- confirm intended provenance fields remain present;
+- check for silent loss of expected monographs, sections, tables, formulas,
+  or source references when the task could affect them;
+- avoid whole-document claims when only sample validation was performed;
+- list anything not tested, not measured, blocked, or still uncertain.
+
+If only part of the task is complete, report the completed and incomplete
+parts separately — don't hide failing tests, unexpected counts, incomplete
+coverage, or contradictory evidence to present a cleaner status.