perf(http): remove legacy hyper 0.14 from deno_http (#34557)

## Summary
- Migrates the legacy `Deno.serveHttp` server path in `deno_http` from
the old hyper 0.14/http 0.2 stack to the existing hyper 1/http 1 stack.
- Removes the legacy hyper/http aliases once the source no longer needs
them, dropping the duplicate HTTP dependency tree from the production
graph.
- Preserves the existing public ops and JavaScript `HttpConn` behavior,
including websocket upgrades and shutdown handling.

## Validation
- Ran focused HTTP and websocket tests covering the migrated legacy
serveHttp behavior.
- Verified `cargo tree` no longer resolves `hyper@0.14`, `h2@0.3`,
`http@0.2`, or `http-body@0.4` through the production `deno` graph.
- Built `deno` in debug mode on the same target and compared binary size
before and after the change.

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Co-authored-by: Nathan Whitaker <nathan@deno.com>