feat(teams): the reconciler, its four refusal gates, and ctx.teams (API 1.6.0)

Core's projection of the module's Teams, kept in step (docs/website/TEAMS.md
§2.4), plus the two ctx members a module pushes through.

The four gates are the file, and each is invariant 1 in a different costume --
module unavailability is staleness, never emptiness:

  1. getTeams() not ok           -> record the failure, touch NOTHING, return.
  2. ok but empty, core holds >=1 -> quarantine; apply only if the NEXT
                                    authoritative answer, an interval later,
                                    agrees.
  3. getTeamMembers() not ok      -> that Team's roster untouched and stale; the
                                    other Teams sync normally.
  4. ok but zero members, had some -> the same two-strikes quarantine, per Team.

Gates 2 and 4 exist because an authoritative-looking empty answer during a cold
start is the one failure indistinguishable from a real wipe. "Every Team on the
shard disbanded at once" costs one interval to confirm; getting it wrong empties
every roster on the site.

Events are an optimisation, never the source of truth. Member and leadership
deltas apply at once for a Team core already knows; team.created and
team.disbanded only ask for a run. §2.2 scopes archival to an authoritative full
list, so a repeated or spurious disband event costs a reconcile rather than a
Team -- and a Team invented from a delta would have no name, no roster and no
leaders anyway.

Two columns TEAMS.md did not contemplate, both on `teams`:

  - roster_synced_at, because team_sync_state holds one row per MODULE and gate 3
    leaves ONE Team behind while the others sync. Without a per-Team stamp that
    Team's page would report the module's last success as its own -- exactly the
    staleness the gate exists to surface.

  - members_empty_since, gate 4's per-Team quarantine. The twin of
    team_sync_state.pending_empty_since, which is per module and cannot express it.

One real bug found by its own test. The roster upsert was writing is_leader, so a
refused getTeamLeaders() left every member demoted -- the roster had already
written `leader: false` before the authoritative call was even made. §2.5 is
explicit that path 2 is answered by getTeamLeaders(), so is_leader is now set on
INSERT only (seeding a Team so it is not leaderless while that call fails) and
moved afterwards by setLeaders() alone. Two writers for one column was the whole
defect.

MODULE_API_VERSION 1.6.0 on both halves -- they state one contract and a module
declares one coreApi range. The number covers the whole Team surface per Part 11;
the members arrive by phase. registerTeamProvider, ctx.teams.publish and
ctx.teams.reconcile are live. ctx.teams.activity.push (§4, phase 3) and
api.registerSlashCommands (§7.1, phase 7) are present and THROW with a sentence
naming their phase, rather than being absent or silently accepting data into
tables that do not exist yet.

39 tests here, and the ctx surface guard in moduleLoader.test.js updated -- it
caught the addition, which is what it is for. Server 809 passed, client 192
passed, 0 failed.

Refs docs/website/TEAMS.md §2.2, §2.3, §2.4, Part 11, Part 12 phase 2

Co-Authored-By: Claude <noreply@anthropic.com>

client/src/modules/version.js

@@ -11,6 +11,13 @@
 // that the two files can drift, so a test asserts they agree
 // (client/test/moduleRegistry.test.js) rather than trusting a bump to remember
 // both.
+// 1.6.0 — the Team surface (docs/website/TEAMS.md Part 11). Nothing on this half
+// changed yet: the two client additions the version covers are the `team.overview`
+// and `team.member.row` slots, and a slot can only be declared by the page that
+// hosts it, which lands with the Team pages in phase 3. This file bumps anyway,
+// for the reason at the top — the two halves state ONE version, and a module
+// declares one `coreApi` range against both.
+//
 // 1.5.0 — `PublicLayout` takes an optional `shell` prop ('narrow' | 'mid' |
 // 'wide') that renders the `shell-… page-body` wrapper core's own pages write by
 // hand. Additive: omitting it is 1.4.0's behaviour, so §3.4's "changing a kit
@@ -38,4 +45,4 @@
 // but the two halves state ONE version: a module declares a single coreApi range
 // and is served one chunk, so a client that claimed 1.0.0 while the server
 // answered 1.1.0 would be two answers to one question.
-export const MODULE_API_VERSION = '1.5.0'
+export const MODULE_API_VERSION = '1.6.0'