1.2.2

• New webhook reporter: native Slack/Discord/Teams/ntfy notifications. A
  fourth reporter joins sentry/mail/shell in every report block: webhook
  sends an HTTP request (POST by default) to a configured URL with a
  jinja2-templated body. The default body is a {"text": ...} JSON payload
  carrying the same subject-plus-body text as the default mail/sentry
  templates, JSON-encoded with jinja2's tojson filter so quotes, newlines,
  and non-ASCII job output always produce valid JSON -- point url at a
  Slack, Mattermost, or Teams incoming webhook and it works with no further
  configuration. method, contentType, headers, body, and timeout
  cover everything else (Discord's {"content": ...} shape, ntfy's
  plain-text body and header-driven priority, or your own endpoint). The URL
  resolves like the sentry DSN (value / fromFile / fromEnvVar) and is
  treated as a secret throughout: it is never logged, and the job-set
  fingerprint redacts the inline URL value and all header values (which
  commonly carry Authorization tokens). No new dependency -- outbound
  delivery rides the core aiohttp. Note: because every job's effective
  config gains the new default block, job-set ids change on upgrade;
  replicas must be on the same version to compare ids, as before.

• Unchanged peers now answer gossip polls with a bodyless 304. Every
  /peer response carries a strong ETag (a content hash of the payload),
  and each polling node echoes the tag of the last full body a peer served
  it back as If-None-Match, so a peer whose state has not changed since
  then skips re-sending the full O(members + jobs) JSON: a converged, idle
  cluster's steady-state round costs headers rather than bodies. This is a
  transport optimization, not a protocol change. A 304 is still a fresh,
  mutually-authenticated round trip, and because the tag is content-derived,
  a match proves the peer's payload is exactly the one the poller already
  holds, so the poller replays its cached observation and every gate (mutual
  agreement, conflict detection, the cluster.driftAfter debounce) advances
  exactly as if the identical body had been re-sent. The one live field, a
  job's seconds-to-next-fire countdown, is hashed as the absolute next-fire
  time instead, so the tag stays stable between fires and rolls exactly when
  a schedule fires. Mixed fleets degrade safely during a rolling upgrade: an
  older peer ignores If-None-Match and keeps serving full bodies, a
  tagless response stops the poller from sending the header at all, an
  unsolicited 304 is recorded as a failed poll, and an over-long or
  non-printable tag is never stored or echoed.

• Fleet-view countdowns are aged, not frozen. With 304 rounds
  refreshing a peer's liveness without re-shipping its job summaries, a
  stored snapshot can now legitimately outlive many polling rounds, so
  GET /fleet re-derives each peer job's advertised scheduled_in
  countdown from the snapshot's age (an elapsed duration measured on the
  local clock alone, so peer clock offsets never leak in) instead of serving
  the value the snapshot arrived with, clamping at zero. The fire itself
  rolls the peer's ETag, so the next poll ships a full body carrying the
  real successor value.

• /peer bodies that do go out are gzip-compressed once they reach
  1 KiB (below that, the per-request CPU spend outweighs the few bytes
  saved). The polling side already advertised gzip support, and the existing
  response-size cap applies to the decompressed payload, so compression
  does not weaken it.

• Dashboard: the version and job-set id header chips copy their value on
  click. Header text is chrome and is no longer text-selectable; the two
  values worth grabbing hand themselves out instead. Clicking the version
  chip copies the version, and clicking the job-set chip copies the full
  job-set id even though the header shows only a short prefix; both
  tooltips say so. The command palette carries the same two copies, so both
  values stay reachable from the keyboard.

• Dashboard: the quick "power-on sweep" flash between boots is gone. The
  full POST boot screen still replays once its cooldown elapses, but the
  visits in between now start the app directly instead of playing a
  full-screen power-on animation first.

• Internal: the conditional exchange ships with a matching batch of cluster
  tests (tag stability across countdown ticks and rollover on a fire, the
  304 replay path, unsolicited-304 and unusable-tag rejection, countdown
  aging, and an end-to-end mutual-TLS 304-plus-gzip round), and the wiki's
  Architecture and Internals page documents the exchange.

Full Changelog: 1.2.1...1.2.2