refactor: dedupe sentry trace

[gambinish]

Explanation

Gaps to close (likely in the sibling client PRs, not core)

• late_success/late_error is the taxonomy used, rather than timeout so some dashboards may need to be updated.
• docs/perps/perps-sentry-reference.md (mobile) still needs updating to describe the new controller-owned trace semantics and the removal of the toast trace.
• removing usePerpsMeasurement({ traceName: PerpsOrderSubmissionToast }) from usePerpsOrderExecution.ts, deleting the PerpsOrderSubmissionToast TraceName from app/util/trace.ts, and the mobile-side Promise.race.
• the core tests cover the meaningful equivalents (fast/late success, fast/late error). The literal "timeout" and "navigation-away" cases don't apply in core; that's fine, but the epic's mobile PR should still cover navigation-away at the UI layer if any UI tracing remains.

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Medium Risk
Changes order-placement tracing and timing behavior on a critical trading path; behavior intentionally avoids cancelling in-flight orders but dashboards and mobile UI must align on late_* reasons instead of client timeouts.

Overview
TradingService.placeOrder now treats PlaceOrderTimeoutMs (60s) as an observational threshold only: a timer fires a warning breadcrumb and flags slow submissions, but the code still awaits provider.placeOrder to completion (no client-side cancel / Promise.race), avoiding UI “failed” while HyperLiquid may still accept the order.

endTrace payload gains optional reason: late_success / late_error when the provider finishes after the threshold, otherwise error on failures; timers are cleared in finally.

Adds PERPS_CONSTANTS.PlaceOrderTimeoutMs, removes unused Perps Order Submission Toast from PerpsTraceName, changelog updates, and TradingService.placeOrder.timeout.test.ts for fast/late success and error paths.

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