[Feat] Let deployment admins turn Voice off when the key comes from the environment

[mrubens]

Summary

When the Voice key comes from R_VOICE_OPENAI_API_KEY (a self-hosted operator's key, or the fleet-wide key Cloud now installs on managed deployments), Voice was forced on: the key resolver returned the environment key before consulting the deployment's enablement, and the Settings card hid every control behind a "configured by the environment variable" line. A deployment admin had no way to turn it off.

This separates the two concerns. The environment key decides which OpenAI account pays for Voice; the deployment's admins decide whether Voice is on, using the same per-deployment enablement every other integration has.

Changes

• lib/server/voice.ts: resolveVoiceOpenAiKey honors the deployment's Voice enablement for the environment key too. The enablement is read on every call (one indexed read) so a toggle applies immediately; only the environment key value itself stays cached.
• trpc/commands/mcp-connections: getVoiceConnectionCommand reports enabled so the card can offer the switch (no enablement row means on). setDeploymentMcpEnabledCommand accepts enabling Voice without a stored connection when the environment provides the key, and does not delete a stored key when disabling in that case, so the deployment falls back to its own key if the environment key is ever removed.
• Settings › Integrations: the environment-keyed Voice card shows Enable Voice / Disable Voice for admins and nothing for members. The "Configured by the R_VOICE_OPENAI_API_KEY environment variable." line is gone. The Settings-keyed path is unchanged.
• The shared integration-status invalidation now includes the Voice connection query so the card flips right after the toggle.
• Docs updated; changeset added.

Tests

• Key resolver: environment key with enablement off returns nothing; on or missing returns the key; the stored connection is never read.
• Enable mutation: without an environment key Voice still requires a stored connection (existing behavior); with one, enabling succeeds with no connection row, disabling keeps a stored key and records enabled: false, and the connection query reports enabled: false.
• Settings card: admins see Disable Voice (no environment-variable text), clicking it calls the mutation and toasts; a disabled deployment shows Voice under Available with Enable Voice; members get no switch.
• Invalidation helper covers the added query.

pnpm lint:fast and web tsc --noEmit pass.

[roomote-community]

No code issues found. See task

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