v0.9.59

- Fix: an incremental rebuild no longer drops cross-file `concept` nodes from files it didn't touch — global dedup during a merge now protects existing nodes from untouched files instead of collapsing same-labeled ones across them (#3477, thanks @hopstreax).
- Fix: extraction now falls back to sequential in-process work when the process pool cannot start (e.g. POSIX semaphore exhaustion), instead of aborting the whole run (#3497, thanks @curtismu7).
- Performance: Python symbol resolution is roughly 47% faster — path resolution is memoized, each file parses once across both resolution passes, and the tree walk is iterative rather than recursive; extraction output is unchanged (#3500 / #3501 / #3502, thanks @abhay-codes07).
- Fix: `graphify explain` now accepts a `path::Symbol` form to disambiguate a symbol that shares its name with its file, and the ambiguity hint now shows a form the resolver actually accepts (#3485, thanks @ayushcodes10).
- Fix: the git hook now keeps its rebuild root inside the repository — a committed `.graphify_root` pointing outside the worktree is ignored and falls back to the repo top, so a checked-in marker can't steer the hook to scan or write outside the tree (#3265, thanks @ayushcodes10).