refactor(frontend): remove v1 settings query gates

[saurya]

HUMAN:

• A human has tested these changes.

AGENT:
OpenHands

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Why

All new conversations use V1, but conversation hooks and provisioning start-task queries were still disabled by the legacy v1_enabled setting. An explicit false value could therefore hide V1 state for conversations that were created through V1.

Summary

• Fetch conversation hooks without consulting v1_enabled.
• Always query V1 conversation start tasks and retain existing status filtering.
• Add focused React Query hook coverage.

Issue Number

N/A

How to Test

• cd frontend && npm test -- __tests__/hooks/query/use-conversation-hooks.test.tsx __tests__/hooks/query/use-start-tasks.test.tsx
• cd frontend && npm run lint
• cd frontend && npm run build
• pre-commit run --config ./dev_config/python/.pre-commit-config.yaml

Video/Screenshots

Not included; this changes query gating without changing rendered layout.

Type

• Bug fix
• Feature
• Refactor
• Breaking change
• Docs / chore

Notes

Stacked on #213. OpenHands/OpenHands (Agent Canvas) already has no v1_enabled dependency in the equivalent hooks, so no Canvas PR is required.

This PR was created by an AI agent (OpenHands) on behalf of the user.

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Enterprise server image for this PR:

ghcr.io/openhands/enterprise-server:sha-68a64f0

[github-actions]

Coverage report

This PR does not seem to contain any modification to coverable code.