feat(cli): stream — a film or a song played in a media player

`meshbay-cli stream PATH` serves one video or sound file over HTTP on
127.0.0.1 for VLC, mpv or any player that reads HTTP; `--player PROGRAM`
starts the player, and closing it stops the stream, as Ctrl+C does.

The file goes as the node stores it: no remux, no transcode, no stream
slot on the node. Byte ranges are answered from leaseless file_req chunks
decrypted in memory, eight ahead and the last 24 kept. Loopback only, a
random token in the address, a foreign Host refused (DNS rebinding), an
audio or video type with nosniff. The connection is pinged and reopened
when it dies; a refusal by the node stops the stream (exit 5).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/docs/USERGUIDE.md b/docs/USERGUIDE.md
index 5b6f77a..93205d3 100644
--- a/docs/USERGUIDE.md
+++ b/docs/USERGUIDE.md
@@ -245,6 +245,7 @@ meshbay-cli chat Family -m "On my way"  # post one (-m - reads it from stdin)
 meshbay-cli chat Family --follow        # then each new message, until Ctrl+C
 meshbay-cli chat                        # interactive: pick a group, talk, Esc to leave
 meshbay-cli get -R Family/photos/2024   # download, here; -o elsewhere
+meshbay-cli stream --player vlc 'Family/films/Night Drive.mkv'   # play it; Ctrl+C stops
 meshbay-cli put -R ~/scans Family/documents
 meshbay-cli rm Family/documents/old-draft.odt   # asks first; --yes in a script
 meshbay-cli logout
@@ -254,7 +255,10 @@ A group is named as the GROUP column of `meshbay-cli groups` prints it; add
 `@owner` only when two of your groups share a name. Quote wildcards
 (`'Family/music/*.flac'`): they are matched against the group, not against
 your disk. An interrupted download resumes where it stopped the next time you
-run the same `get`. `rm` deletes what you uploaded, from any of your devices;
+run the same `get`. `stream` plays a film or a song without downloading it:
+it prints an address to open in VLC or mpv (or starts the player with
+`--player`), which works on this computer only and until you press Ctrl+C or
+close the player; skipping ahead in the player works. `rm` deletes what you uploaded, from any of your devices;
 the node's operator can delete anything. Run `meshbay-cli` with nothing after it for a two-pane
 view: this computer on the left, your groups on the right, F5 to copy the
 selection across, Delete to delete it from the group (what `rm` may delete).