chore(release-next): release 3.0.0-alpha.4

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3.0.0-alpha.4 (2026-06-13)

Features

• docs: Add 'When to Use' page and nav link (bd5c6f3)

Bug Fixes

• client: bound HTTP/1.1 request body pump with outbound flush backpressure (c76e9ee)
• client: stamp cancellation token into request options before channel enqueue (28d422d)
• h3: dispose decoded frames and copy blocked QPACK header blocks (e51ab5d)
• http2: stop returning in-use body-drain buffers to the shared pool on teardown (19b83c5)
• server: guard buffered body fast path and serve single-segment bodies zero-copy (3358b02)
• server: remove response data-rate entry when body completes (61a4b1e)
• server: serialize HTTP/1.x pipelined dispatch and fix WirePipeliningSpec under-read (3429403)

Performance

• h3: decode inbound frames zero-copy from the transport buffer (1171012)
• server: deduplicate data-rate timer scheduling and reuse response pipe writer (0c0e157)

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