docs(changelog): stamp #6944 + add ambiguous-suffix-match regression test

Codex round-2 SHOULD-FIX: add a committed test asserting the hinted bare-id
fallback returns null when two same-provider options normalize identically
(refuses to guess), plus single-match resolves and exact-match unaffected.
Additive test-only; no behavior change to the contributor's fix.

Co-authored-by: josephcy95 <josephcy95@users.noreply.github.com>

CHANGELOG.md

@@ -5,6 +5,7 @@
 
 ### Fixed
 
+- **Custom-provider models keep their exact identity across catalog refreshes.** When a session used a model served through a custom provider whose upstream id contains a namespace (e.g. `z-ai/glm-5.2` under a `tokenrouter` custom endpoint), a catalog refresh could mis-resolve the picker selection — matching a *different* model whose bare suffix collided, or (in an interim fix) fabricating a new bare-id option instead of re-selecting the real one. Model resolution now matches the exact routed id first, and only falls back to a provider-hinted bare-id repair (preserving the older #6195 behavior for legacy sessions that stored just the suffix) when there is exactly one unambiguous candidate — otherwise it declines to guess. The resolved value is always an existing dropdown option, so re-renders no longer inject duplicates or lose the selection. Thanks @josephcy95. (#6944)
 - **WebUI no longer crashes a send when running against an older hermes-agent.** The streaming path passed `persist_user_timestamp=` to `agent.run_conversation()` unconditionally, so a WebUI paired with an older agent whose `run_conversation()` predates that keyword raised `TypeError: unexpected keyword argument` and the message failed. The three call sites now check the callable's signature first (via a small `_supports_kwarg` introspection helper) and only pass the timestamp when the agent accepts it — the same defensive pattern already used for `moa_config`. Modern agents are unaffected (the timestamp is still passed with the identical value); older agents degrade gracefully instead of erroring. Thanks @harsh2hell. (#6935)
 - **`hermes sessions list` no longer shows blank titles for WebUI sessions.** Background title generation wrote the auto-title to the WebUI session sidecar but never to hermes-agent's `state.db`, so the CLI/TUI session list showed those WebUI sessions untitled. The title is now bridged into `state.db` after it's generated (and on adaptive refresh) via `set_auto_title_if_empty`, which respects title provenance — a name you set manually via CLI/Gateway/TUI (`user` source) is never overwritten by the auto-title, an already-auto-titled row stays put, and an existing session's `source` is preserved (the sync creates the row with INSERT-OR-IGNORE semantics). Thanks @liuguangyong93. (#6892)
 - **No more phantom "Compressing context" barrier after switching sessions.** The compression UI state is per-session, but `loadSession()` did not clear it on a switch, so a compression card from a prior session could leak across the load and appear as a phantom "Compressing context" barrier on a fresh session that never triggered compression. Switching sessions now clears the compression UI (state, elapsed timer, composer session-lock, and barrier element) alongside the other per-session resets, before the transcript loads. A compression genuinely running on the session you switch *to* is unaffected — it re-surfaces from that session's own live event stream (and manual compression from its server job status). Thanks @happy5318. (#6938)