Release PJ (v0.51.449): stop recovered turns replaying into later context (#4283) (#4291)

* stage-4286: stop recovered turns replaying into later context (fixes #4283)

* Release PJ: stop recovered turns replaying into later context (#4283)

rodboev's #4286. Codex SAFE + Opus net-positive-and-safe + 9152/0 clean suite.
Single-row prefix allowance gated to _recovered+role==user+offset0.

Co-authored-by: rodboev <rodboev@users.noreply.github.com>

---------

Co-authored-by: nesquena-hermes <agent@nesquena-hermes>
Co-authored-by: rodboev <rodboev@users.noreply.github.com>

CHANGELOG.md

@@ -7,6 +7,12 @@
 
 - **Windows pytest-harness compatibility (#3664).** Hardened the test suite to run on Windows: profile-home fallback paths are path-normalized, strict POSIX file-mode (`0o600`) assertions are gated behind `os.name != "nt"` (Linux still asserts them at full strictness), the conftest cleanup handles Windows process-tree/port teardown and the Py3.12+ `shutil.rmtree` `onexc` shim, and tests that require `fork`/`fcntl` carry `@requires_fork` / `@requires_fcntl` markers (which never skip on Linux). Test-only — no runtime or app behavior change, no Linux CI behavior change. (#4254, #4255, #4256, #4257, #4259, #4263, #4266, #4274)
 
+## [v0.51.449] — 2026-06-16 — Release PJ (stop recovered turns replaying into later context)
+
+### Fixed
+
+- **Interrupted conversations no longer replay the prior message into every later turn.** After a session was interrupted (gateway restart or tool-iteration limit) and recovered, the WebUI could re-inject the recovered user message into the context of each subsequent turn. The state-database context reconciliation now recognizes a recovered turn as a valid single-row aligned prefix (gated strictly to a recovered user turn at the head of the window), so it's matched and de-duplicated instead of replayed. (#4283)
+
 ## [v0.51.448] — 2026-06-16 — Release PI (fix blank transcript viewport regression)
 
 ### Fixed