status

var (
	// ErrClosed means the write face is fail-closed: the vault contract failed
	// to load, or its pinned root capability has been closed. Reading tolerates
	// a missing contract; a write without one could destroy a file.
	ErrClosed = errors.New("write face is closed")
	// ErrArtifactPolicyUnavailable means the core contract loaded but its
	// artifact policy is unavailable, so instance writes cannot be classified.
	ErrArtifactPolicyUnavailable = errors.New("artifact policy unavailable")
	// ErrNonInstance means the requested path is a readable artifact rather
	// than a governed note instance.
	ErrNonInstance = errors.New("target is not a governable artifact")
	// ErrOutsideKnowledgeScope means the requested path is a note the lifecycle
	// never reaches: it lies outside the directories scan.knowledge_dirs names
	// as the knowledge layer, and the state machine runs only there.
	ErrOutsideKnowledgeScope = errors.New("target is outside the knowledge layer scan.knowledge_dirs declares")
	// ErrInvalidPath means a status request did not name a local vault-relative
	// slash path.
	ErrInvalidPath = errors.New("invalid vault-relative path")
	// ErrStale means the submitted form's "from" no longer matches the note's
	// on-disk status: the page was loaded before someone else changed the file.
	ErrStale = errors.New("note is stale, reload and try again")
	// ErrConcurrentWrite means the file's identity, mode, mtime or bytes
	// changed between Flip's descriptor read and its pre-write recheck. It is
	// distinct from ErrStale and does not satisfy errors.Is(err, ErrStale).
	ErrConcurrentWrite = errors.New("note changed while flipping")
	// ErrContentChanged means the note's bytes no longer carry the content
	// identity the caller read: something outside the status line was edited
	// after the page rendered. The status line's own divergence is ErrStale.
	ErrContentChanged = errors.New("note content changed after it was read")
	// ErrStatusLine means the frontmatter block does not contain exactly one
	// line beginning with "status:". yomihon reports; a human edits the file.
	ErrStatusLine = errors.New("frontmatter does not have exactly one status line")
	// ErrPublishedReserved means the flip named published as its target. That
	// status records a completed publication outside the vault, which nothing
	// here can attest, so the value enters a note only by hand.
	ErrPublishedReserved = errors.New("published records a completed publication and no publisher exists to attest one")
	// ErrStatusSyntaxUnsupported means the reader understands the note's
	// status but the frontmatter writes it in a form the surgical rewriter
	// cannot preserve — an explicit or quoted key, a flow mapping, an anchor
	// the rewrite would sever. The note is refused unchanged.
	ErrStatusSyntaxUnsupported = errors.New("frontmatter writes status in a syntax the surgical rewriter does not support")
	// ErrDurabilityUnsupported means the platform cannot prove an atomic
	// rename's directory entry reached durable storage, so the write face
	// refuses rather than leave new bytes a crash could silently discard.
	ErrDurabilityUnsupported = errors.New("durable install is unsupported on this platform")
	// ErrInstallStranded means another program edited the note inside the
	// install window and the edit could not be put back under the note's own
	// name. Both versions are on disk, one named in the error, and nothing was
	// removed. Unlike ErrConcurrentWrite it cannot say which the note carries.
	ErrInstallStranded = errors.New("an edit raced the flip and both versions were left on disk")
	// ErrInstallUncertain means the atomic replacement completed but the
	// containing directory could not be synchronized, so the new bytes are
	// visible without their survival across an immediate crash being confirmed.
	ErrInstallUncertain = errors.New("note rewritten but durability was not confirmed")
)