v0.2.9

The note walk no longer has a size ceiling.

find-md-files-recursive folded a directory's entries with fold-right, which is not tail recursive, so it burned one interpreter stack frame per file. Past roughly 1011 entries in a single directory the walk blew the stack -- and because every tool that enumerates notes starts there, no fresh server could finish starting, while a warm one lost note-links, status and note-rename and kept everything that addresses a note by path.

The walk is iterative now; depth is the directory nesting depth rather than the file count. Verified with all 2460 notes of a real corpus in one flat directory, and the enumeration output is byte-identical to before.

Also: a tool call that dies mid-flight now reports instead of dropping its response, so a caller is never left unable to tell failure from slow.

Known issue: note-rename is not atomic. It renames the file, then rewrites crosslinks with no transaction or rollback.