Remove legacy Code Everywhere remote inbox HTTP path

[cbusillo]

Summary

• remove the archived Code Everywhere HTTP polling adapter from the TUI remote inbox client
• keep the active Every Code / Discord WebSocket bridge path and timeline fanout
• preserve legacy remote_inbox.code_everywhere_url configs and CLI overrides only when they point at a WebSocket bridge URL; legacy HTTP polling URLs now warn and do not silently pretend to work
• update repo workflow metadata away from Code Everywhere wording

Refs #19

Note: the non-runtime chatwidget smoke-helper rename was intentionally left out of this PR because touching code-rs/tui/src/chatwidget.rs trips the repo blob-size policy. The runtime remote inbox cleanup, explicit HTTP retirement behavior, and WebSocket compatibility path are covered here.

Validation

• ./build-fast.sh
• just local-code-rebuild
• local DUI bridge smoke with remote_inbox.bridge_url: hello, heartbeat, command_ack, returncode 0
• local DUI bridge smoke with legacy remote_inbox.code_everywhere_url using ws://: hello, heartbeat, command_ack, returncode 0
• cd /Users/cbusillo/Developer/discord-blue && uv run python -m unittest tests.test_every_code