M1I04: Connection wrapper

[s2x]

What it builds

src/Server/Socket/Connection.php — Wraps an accepted connection's \Socket resource:

• read(int $length = 65536): string|false — returns false if closed
• write(string $data): int|false — returns false if closed
• close(): void — idempotent, sets $closed = true
• isClosed(): bool
• getPeerName(): array — ['host' => '...', 'port' => 123], throws if closed or fails
• getLastActivity(): float — microtime(true) of last successful read/write, for timeout detection
• setOption(int $level, int $option, mixed $value): void — silently returns if closed
• lastActivity updated only on successful read/write ($data !== false / $result !== false)

Files to create

Action	Path
Create	src/Server/Socket/Connection.php

Tasks from PR #58 review

#	Task	Status
1	getPeerName(): closed check + return value validation	✅ Done (#58, 71e8fa2)
2	lastActivity only updated on successful read/write	✅ Done (#58, 71e8fa2)
3	setOption() return value validation in both Connection and Socket	✅ Done (#58, 71e8fa2)
4	Add ConnectionTest with coverage for all methods and closed-socket paths	⬜ To do
5	testCloseIsIdempotent assertion	✅ Done (#58, 71e8fa2)
6	testAcceptReturnsConnection uses Socket API instead of raw functions	✅ Done (#58, 71e8fa2)

Dependencies

None (pure wrapper around \Socket).

References

• Spec: Connection section
• Plan: Task 4
• Milestone doc: docs/superpowers/milestone-1/04-connection.md