v0.6.0

Tracks epubveri from 0.5.15 to 0.9.7, which corrects a false positive
epubsana had been repairing, and closes the only regression epubsana introduced
on the shared shelf.

Changed

• epubveri 0.9.7 is now the minimum, and the reason is correctness.
  opf.content_document.empty_title was an EPUB 3 rule firing on EPUB 2 books
  (XHTML 1.1 types <title> as <text/>, which RELAX NG matches on empty; the
  non-empty assertion exists only in epub-xhtml-30.sch). While epubsana ran
  against the 0.5 line, fix.empty_title therefore filled <title> elements in
  books that were already valid. Measured on the 94-book shared shelf, epubsana's
  code unchanged and only the detector moving: 606 proposals → 3 (the three
  remaining are one EPUB 3 book, where the rule is right), and books receiving
  any proposal at all fall from 23 to 13. Upstream counts 8 books going INVALID →
  VALID for this cause alone.

  No epubsana code was wrong and no epubsana test could have caught it: a
  repairer inherits its detector's false positives whole. The bump itself needed
  no source change — the 0.8.0 Options API break does not reach this crate.

• The bare-text fixer follows its finding to a new home. epubveri removed
  htm.epub2_dom.bare_text_in_body in the 0.9 line because it duplicated the
  RELAX NG grammar; the same defect now arrives as
  opf.content_document.schema_violation with the message stray text is not
  allowed directly in "body". fix.bare_text_in_body matches that shape
  (message prefix and params[0] == "body", since one rule now spans a whole
  grammar) and is otherwise unchanged. Stray text in any other container —
  an <ol>, say — is declined: the correct wrapper there is an <li>, which
  asserts the text is a list item, and that is a judgement rather than a
  determinate repair. On the shelf the fixer clears 289 findings across 17
  documents; without the re-target it would silently have done nothing.

Added

• Two fixers, from the families epubveri's 0.9 work newly exposed (nineteen →
  twenty-one). Both were specified in docs/FIXERS.md before being coded, and
  both are one message shape wide rather than one rule wide — the unit that
  replaces "family" now that so much detection lives in the grammar.

  • htm.obsolete_attribute, the legacy <a name> anchor (fix.anchor_name,
    AutoSafe) — name on <a> predates id and XHTML 1.1 removed it. Where
    the element already carries an id with the identical value the anchor is
    declared the modern way too, so the name is a duplicate declaration and
    every #fragment targeting it resolves through the id. Dropping it loses
    nothing, which is what makes this the rare deletion that is AutoSafe.
    Declines an anchor with no id (renaming name → id would have to
    prove the value is an NCName and unique — it can manufacture a finding), one
    whose id differs (dropping breaks the fragment; an element cannot carry two
    ids), and every other attribute in the family, <br clear> included: its
    presentational intent has no single markup equivalent.

  • An empty lang / xml:lang (fix.empty_lang, ConfirmNeeded) — EPUB 2's
    grammar types them as a language tag and "" is not one. The attribute is
    deleted. It is deliberately not AutoSafe: an element that declared
    "undetermined" will now inherit its parent's language, and a reading system
    acts on that (hyphenation, text-to-speech, CJK font selection). XHTML 1.1 has
    no valid spelling for "undetermined", so the choice is between an invalid
    document and inheritance — a decision about the book. A malformed tag
    (lang="en_US") is declined: repairing it means guessing.

  On the 94-book shelf the two clear exactly the 442 findings they target
  (162 + 280) and no others, take one more book to fully valid, and introduce
  nothing. Both are single-book shapes on this shelf, which shows the repair is
  right for that shape rather than that the shape is common — the declines above
  are what makes that an acceptable basis to ship on.

• fixers::handled_rules() — every epubveri rule some fixer knows how to
  address. "Knows how to" is not "will": a listed rule may still be declined on
  any given book, and the distinction is the point. A rule missing from the
  list is a coverage gap; a listed rule that proposes nothing is a decision, and
  reading a plan's output cannot tell the two apart — a fixer that declines
  everywhere looks exactly like a fixer that does not exist. An embedder deciding
  whether to route a book through epubsana at all can now ask without running a
  plan.

Fixed

• fix.manifest_dangling_item no longer drops the navigation document. A
  dangling manifest item carrying properties="nav" was dropped like any other,
  which cleared RSC-001 and produced opf.package.missing_nav_document in its
  place — a book no more valid than before, and now without a table of contents.
  It declines instead, on the same principle as the existing spine guard: a
  repair that trades one error for another is not a repair. The nav token is
  matched, not the substring, and a declined item is also removed from the shared
  spine guard's arithmetic (that guard counts deletions that could happen, and
  this one no longer can).

  This was epubsana's own defect, live since 0.4.0 and present under both the old
  and the new detector. It was the only finding epubsana introduced anywhere
  on the 94-book shelf; with the guard in place the shelf run introduces nothing.

Full notes: CHANGELOG.md. Also on crates.io.