Lifecycle and safety fixes from the external review:
- Observe abort while awaiting the initialize handshake, so a server that never
replies can't defeat the tool-timeout signal.
- On an aborted request the server won't cancel, tear the instance down after a
bounded grace instead of releasing the serialized queue with work still live
(prevents overlapping document lifecycles).
- Re-check provider disposal after the canonicalize/read awaits so a query can't
spawn an unowned server after disposeAll().
- Read the source through one open handle (stat + read on the same fd) to close
the realpath-vs-read TOCTOU; decode with a fatal UTF-8 decoder so a legitimate
U+FFFD is not misclassified as invalid.
- Validate and read the source BEFORE spawning a server (pre-start rejection).
- Require an explicit openClose for option-form textDocumentSync.
- Reject nonpositive teardown budgets and non-executable absolute commands at
load; surface unsupported operations as structured LSP_UNSUPPORTED_OPERATION.
- Retain the stderr tail (fatal diagnostics land at exit), not the prefix.
- Catalog the seam vocabulary in docs/core-data-structures/lsp.md.
8e8f90e235