Define explicit ownership for custom appenders and formatters

Add SharedLogState for synchronized value data and factories for
independently owned appender state and captured formatter closures.
Reject unsafe configuration state, update the test collector to value
snapshots, and document the breaking APIs in version 3.0.0.

Expand ORC ownership and sanitizer coverage and reject stale test
executables.

tests/README.md

@@ -9,12 +9,15 @@ Run from the repository root:
 | --- | --- |
 | `nimble test` | All unit, regression, and ThreadSanitizer tests under ORC with threads enabled |
 | `nimble testUnit` | Existing embedded unit tests |
-| `nimble testRegression` | Handle lifetime, configuration freshness, refresh failure recovery, appender-state cleanup, and writer shutdown |
-| `nimble testThreadSafety` | Separate ThreadSanitizer processes for service ownership, last-owner teardown, reconfiguration, custom state, and formatter closures, plus an independent-service control |
+| `nimble testRegression` | Custom-state/formatter ownership, handle lifetime, configuration freshness, refresh failure recovery, appender-state cleanup, and writer shutdown |
+| `nimble testThreadSafety` | Separate ThreadSanitizer processes for service ownership, last-owner teardown, reconfiguration, shared state, factory state, formatter closures, collector snapshots, timestamps, and the Nim allocator, plus an independent-service control |
 
 `nimble test` attempts every suite even if an earlier suite fails to compile or
 run, summarizes the failing suites, and exits unsuccessfully if any suite fails.
 The subset commands use the same build and execution procedures as the full run.
+Old executables are removed before compilation, and a new executable must exist
+before a suite runs. This prevents stale binaries from hiding compilation errors
+when a nested Nimble command fails to propagate its exit status.
 
 Executables are generated in ignored `tests/bin/`. The shutdown child is built
 with `-d:multithreaded`; `--threads:on` alone does not enable background writers.
@@ -39,13 +42,43 @@ Thread arguments contain borrowed pointers so no hidden owning argument keeps
 the service alive. Atomic construction/destruction counters verify that every
 tracked appender is released exactly once after the workers join.
 `service-reconfigure` exercises concurrent updates and local cache refresh.
-The other scenarios retain parent owners until all workers join. Custom-state
-and closure tests only read application data; their concurrent writes are the
+`shared-state-lifetime` drops the original state handle before concurrent
+mutations and verifies one final destruction with all updates present.
+`formatter-lifetime` drops an already-used original formatter and checks both
+independent closure counters and exact cleanup on worker threads. `factory-state`
+uses per-thread cyclic reference graphs, explicitly runs the ORC collector, and
+checks that each worker maintains its own counter. `collector` concurrently
+records messages containing JSON and exceptions and mutates returned snapshots.
+These ownership scenarios use explicit timestamps where messages are needed.
+
+The separate `timestamp` case exercises concurrent `initLogMessage()` calls. It
+currently exposes a sanitizer report in libc local-time conversion reached via
+Nim's `std/times.now()`; this remains a separate thread-safety issue.
+
+`allocator` calls the standalone reproduction in `runtime_allocator.nim`, which
+imports no logging code. It exercises sequence growth and clearing under a lock
+alongside thread-local closure allocations. On Nim 2.2.10 it reproduces a report
+in `system/alloc.nim`'s `compensateCounters` / shared-free-list path. The same
+runtime report can occur in `factory-state` and other allocation-heavy cases.
+The ten ownership scenarios passed debug and release diagnostic builds with
+`-d:useMalloc`;
+`nimble test` deliberately retains the default allocator and exposes these
+reports rather than suppressing them.
+
+The original custom-state and formatter scenarios retain parent owners until all
+workers join. They only read application data; their concurrent writes are the
 implicit ownership operations caused by cloning and destruction. The independent
 case creates a separate service inside each worker and should pass. Custom-state
 and formatter cloning is serialized with a lock, matching configuration refresh;
 the copied appenders are used and destroyed outside that lock.
 
+`ownership.nim`, imported by `regressions.nim`, checks independent snapshots,
+exception recovery, factory and clone behavior, and the built-in formatter paths.
+Compile-time checks reject direct and nested refs, captured formatter arguments,
+and embedded synchronization primitives. The formerly unsafe custom-state and
+formatter scenarios now exercise the supported shared-handle and factory APIs;
+the unsafe forms are tested as compilation failures.
+
 The in-process regression tests are deterministic. The lifetime suite checks
 copying, self-assignment, replacement, moving, container copies, and exporting a
 handle from a local service. Shutdown tests launch
@@ -55,12 +88,17 @@ real exit hook without sleeps to hide queued-message loss. Like the race tests,
 the shutdown failure can depend on scheduling; a passing run is not proof of
 thread safety or reliable draining.
 
-This suite does not yet force an active producer/channel-close race, separately
-exercise the shared `testutil.LoggedMessages` graph, or exhaust ORC cycle-collector
-interleavings. It provides targeted regressions for the reproduced ownership
-defects and the configuration, cleanup, and shutdown findings.
+This suite does not yet force an active producer/channel-close race or exhaust
+ORC cycle-collector interleavings. It provides targeted regressions for ownership,
+configuration, cleanup, timestamps, allocator behavior, and shutdown.
 
-After the shared-handle implementation, the service sanitizer scenarios, lifetime
-suite, and appender-state cleanup regression should pass. The custom-state and
-formatter sanitizer cases, `isEnabled` freshness, failed-refresh recovery, and
-writer shutdown remain failing regressions for subsequent work.
+The ownership scenarios, lifetime suite, and appender-state cleanup regression
+exercise the new ownership contracts. `isEnabled` freshness, failed-refresh
+recovery, local-time timestamp construction, allocator reports, and writer
+shutdown remain for subsequent work.
+
+The standalone `ownership.nim` regression suite passed AddressSanitizer and
+LeakSanitizer with `--mm:orc -d:useMalloc`. An additional worker-thread build found
+no invalid accesses in the shared-state, factory-state, formatter-lifetime, and collector
+scenarios. LeakSanitizer reported per-thread ORC cycle-registration buffers
+allocated by the Nim runtime; this is not a clean leak-check result.