* Add attach mode
* Better UI
* Remove unnecessary message
* extract + test the docker stream demux; reset terminal mode per session
- Pull the Docker hijacked-stream decoder (HTTP header strip, chunked
decode, 8-byte multiplexed frame demux + raw/TTY fallback) into a pure
src/lib/server/docker-stream-core.ts with unit tests covering raw
passthrough, stdout/stderr demux, frames split across socket events,
a split header, chunked reassembly, and the raw-fallback path.
- vite.config.ts now imports the core instead of carrying its own copy.
server.js runs against ./build and can't import the TS core at runtime,
so it keeps the inline copy with a note to keep the two in sync.
- containers page: default a fresh terminal session to exec so a prior
container's Attach choice (shared terminalMode) doesn't carry over.
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Co-authored-by: Jarek Krochmalski <jkrochmalski@gmail.com>
