fix(core): enforce maxTotalTimeout without progress notifications

[claxman]

Fixes #2695.

maxTotalTimeout is documented as a hard cap, but _setupTimeout only arms timeout. The cap is read in _resetTimeout, which runs only on notifications/progress with resetTimeoutOnProgress set. A request with { timeout: 1000, maxTotalTimeout: 150 } and no progress is still pending at 150ms. inputRequiredDriver hits the same path, since it passes the shrinking remaining budget back into Protocol as maxTotalTimeout.

This arms the pending timer with min(timeout, maxTotalTimeout) when the cap is set, re-arms min(timeout, remaining) on a progress reset, and rejects with Maximum total timeout exceeded plus { maxTotalTimeout, totalElapsed } once elapsed reaches the cap. The driver loop is unchanged. Fixing only the driver would leave a plain request() with maxTotalTimeout still sitting on timeout.

Three cases added to test/shared/protocol.test.ts: cap with no progress, cap with default timeout, remaining budget after a progress reset. Each fails on main.

This change was developed with AI assistance.

[changeset-bot]

🦋 Changeset detected

Latest commit: 3cb2939

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 6 packages

Name	Type
@modelcontextprotocol/core-internal	Patch
@modelcontextprotocol/client	Patch
@modelcontextprotocol/server	Patch
@modelcontextprotocol/codemod	Patch
@modelcontextprotocol/core	Patch
@modelcontextprotocol/server-legacy	Patch

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commit: 3cb2939

[Ricky-7-Yan]

AI-assisted review. I checked the timeout lifecycle against #2695 and the existing cleanup paths. The patch closes both gaps: the initial timer is capped even without progress, and a progress reset uses the remaining total budget rather than restarting the full per-request timeout. The timeout handler preserves the existing RequestTimeout code while reporting which ceiling fired, and the three regressions cover the silent-peer, default-timeout, and reset-after-progress paths. The implementation is focused and all current CI checks are green. I found no blocking issue in the diff.