Adds a deprecation warning callout to the top of the main Coder Tasks
docs page (`docs/ai-coder/tasks.md`).
The message reads:
> Beginning June 2026, Coder Tasks will be deprecated. Support for Tasks
will be maintained on Coder's ESR release and through Coder v2.36. After
v2.36, support for Tasks will only be on our 12-month ESR release for
Coder Premium Customers.
Uses the existing `> [!WARNING]` admonition pattern already used for
deprecations elsewhere in the docs (e.g.
`docs/ai-coder/ai-gateway/mcp.md`).
Linear:
[CODAGT-157](https://linear.app/codercom/issue/CODAGT-157/ensure-docs-are-updated-for-beta)
---
_This PR was opened by Coder Agents on @davidfraley's behalf._
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Co-authored-by: Matt Vollmer <matthewjvollmer@outlook.com>