Use Map-backed cost ledgers so externally derived session and run identifiers never cross ordinary object prototype semantics. Preserve the existing JSON storage format and extend browser and isolated ledger regressions for replay, overflow, legacy data, and reserved keys.
* refactor(model-routing): centralize explicit foreground fallback policy
Make foreground fallback an explicit per-user, availability-only policy shared by streaming Chat, non-stream Chat, and Agent runs.
Preserve strict defaults, owner/model and credential boundaries, pinned Agent routes, and truthful per-round provenance/accounting. Carry provider-reported model identifiers through native streaming adapters, non-stream responses, and caches, and keep legacy default_model_fallbacks as tombstoned raw storage that generic settings APIs and agent tools cannot expose or mutate.
* fix(agent-loop): restore rebase-dropped qwen routing, workspace prompt, and temperature clamp
* fix(model-routing): thread selected endpoint identity, fix cost classification and fallback eligibility
* fix(chat): restore stream helpers and harden run stop lifecycle
* fix(model-routing): let numeric provider codes win over symbolic rate-limit statuses
* fix(agent-loop): apply qwen temperature and notes-tool clamps per fallback candidate
* fix(chat): honor queued stop across resend and reload canonical terminal on EOF
* fix(chat): track stop queue and cleanup ownership by per-send generation
* fix(agent-loop): preserve requested temperature for non-qwen fallback candidates
* fix(chat): reserve send ownership before any await and scope stop to the current send
* fix(chat): clear the previous run identity at send reservation
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Co-authored-by: RaresKeY <158580472+RaresKeY@users.noreply.github.com>
Co-authored-by: StressTestor <212606152+StressTestor@users.noreply.github.com>
Alexandre Teixeira