fix(relay): collapse the duplicated cell-row lock metric declarations

9741c75740 landed six entries where it meant three. My uncommitted copy of the
same change was on disk when the file was staged, so both were captured and
relay_runtime_metrics ended up declaring cell_row_lock_scopes_checked,
cell_row_lock_scopes_stood_down and cell_row_lock_scope_violations twice.

Nothing reports this. An HCL object constructor accepts duplicate attributes and
the last one silently wins -- confirmed against a standalone probe, where
`{ a = "first", a = "second" }` evaluates to "second" and `terraform validate`
returns Success. So the first three declarations were being discarded with no
diagnostic anywhere, which is the same shape of silent-drop failure the guard
these fields measure exists to catch.

Keep one declaration each. Two descriptions are corrected against the emitter
rather than kept verbatim: `checked` counts transactions that evaluated a
relay_cells *write*, not any statement, because CellRowLockScope sets that flag
only on the write branch; and `violations` also counts writes that name no cell,
not only out-of-order acquisitions.

Declaration only -- no apply, and no other change to the file.

cloud/infra/terraform/relay-observability.tf

@@ -98,12 +98,9 @@ locals {
     cell_inventory_holds               = { field = "cellInventoryHolds", description = "Cell-inventory locks acquired in the interval; the percentiles above summarise these." }
     cell_inventory_lock_unavailable    = { field = "cellInventoryLockUnavailable", description = "Fail-fast cell-inventory acquisitions that found the lock held. Includes background sweeps, which step aside by design, so this is contention pressure rather than user-visible failure." }
     cell_inventory_lock_timeouts       = { field = "cellInventoryLockTimeouts", description = "Bounded cell-inventory waits that expired, counted per attempt rather than per request. This is the user-visible lane." }
-    cell_row_lock_scopes_checked       = { field = "cellRowLockScopesChecked", description = "Transactions in which the cell-row lock guard evaluated at least one relay_cells statement. The denominator: zero violations means nothing unless this is non-zero." }
+    cell_row_lock_scopes_checked       = { field = "cellRowLockScopesChecked", description = "Transactions in which the cell-row lock guard evaluated at least one relay_cells write. The denominator: zero violations says nothing unless this is non-zero." }
     cell_row_lock_scopes_stood_down    = { field = "cellRowLockScopesStoodDown", description = "Transactions in which the guard stood down because it could not read a locked row's cell_id. Non-zero is a bug report, not a clean run." }
-    cell_row_lock_scope_violations     = { field = "cellRowLockScopeViolations", description = "Cell-row lock order violations observed in the interval. Warn-only in production; throws in tests." }
-    cell_row_lock_scopes_checked       = { field = "cellRowLockScopesChecked", description = "Transactions in which the cell-row lock guard evaluated at least one relay_cells write. This is the denominator: zero violations only means something while this is above zero." }
-    cell_row_lock_scopes_stood_down    = { field = "cellRowLockScopesStoodDown", description = "Transactions in which the cell-row lock guard could not read a locked relay_cells statement and stopped checking. Any value above zero is a guard bug, not a clean run." }
-    cell_row_lock_scope_violations     = { field = "cellRowLockScopeViolations", description = "relay_cells row locks taken out of ascending cell_id order, or writes naming no cell. Warn-only in production; the per-cell locking conversion is gated on this staying zero against live traffic." }
+    cell_row_lock_scope_violations     = { field = "cellRowLockScopeViolations", description = "Cell-row lock order violations, plus relay_cells writes naming no cell. Warn-only in production, throws in tests; the per-cell locking conversion is gated on this staying zero against live traffic." }
   }
 
   # Regions the director can hint or select. Pinned to relay-contract's RELAY_REGIONS by