v4.6.1

Four latent-bug fixes, none release-blocking on their own but worth a prompt
patch given the severity of the wire-protocol issue:

• Fix (silent data corruption, pre-existing): a hard crash (kill -9,
  power loss, abort — anything that skips a clean shutdown) could leave a
  table's row-id counter stale if fewer than 64 rows had been inserted since
  its last periodic flush. On reopen, the next INSERT would then reuse an
  already-in-use row id, silently overwriting the pre-existing row. Fixed by
  reconciling the counter against the actual max row id scanned whenever the
  index-rebuild-on-open path runs without a valid snapshot (which happens
  precisely on a crash reopen, and is a no-op on a clean one).
• Fix (wire-protocol correctness hazard, pre-existing): the PostgreSQL
  wire handler intercepted any statement whose raw text merely contained
  version(), current_database(), or current_user — anywhere, including
  inside a WHERE clause — and answered with a hardcoded canned reply instead
  of executing the real statement. In the worst case, an UPDATE/DELETE
  referencing one of these in its WHERE clause never executed at all, while
  the client received a reply indistinguishable from a real "0 rows matched"
  result. Fixed by removing the interceptors; the real query engine already
  answers all three correctly and session-aware.
• ~ !~ ~* !~* (PostgreSQL POSIX regex match operators) and the raw
  ~~ ~~* !~~ !~~* operator spellings of LIKE/ILIKE are now
  implemented — previously errored with "Binary operator not yet supported"
  for every case, including in WHERE clauses.
• CREATE SCHEMA name CREATE TABLE ... CREATE TABLE ... (PostgreSQL's
  multi-element schema-creation form) is now accepted — previously any
  statement with more than one embedded element failed to parse entirely.
  Bare names inside the block (including cross-references between sibling
  tables, e.g. REFERENCES/PARTITION OF) resolve into the new schema; the
  whole statement is all-or-nothing (a failure partway through leaves nothing
  behind, matching PostgreSQL).