Video calls (PairUX→ASCII), agent@ chat, and finger routes

ssh video-<code>@ joins a PairUX/LiveKit call rendered as truecolor
ASCII (▀ half-blocks, 2 pixels per cell); video@ prompts for a code.
Codes are minted by PairUX only. Pipeline: VP8 RTP → PLI keyframe
requests → ivfwriter remux → ffmpeg decode/scale → RGB24 → ANSI →
bubbletea over the SSH PTY. Subscriber-only, no audio in v1.

ssh agent@ opens a persisted chat with the operator's agent —
AGENTBBS_AGENT_CMD runs per message (stdin→stdout), e.g. `claude -p`.

ssh <member>@ with someone else's name prints a classic finger card
(.plan, member since, last seen) and disconnects; your own name still
enters the hub.

cmd/lkpublish: dev publisher for testing (explicit -fps pacing; lksdk
IVF replay mispaces from file timebase alone, measured 1fps from a
15fps file; dimensions required or dynacast pauses the track).

Verified end-to-end against livekit-server --dev: 128k truecolor cells
/ 20k distinct colors streamed over a real SSH session; chat round-trip
and finger card verified over SSH. Go toolchain pinned to 1.26 via
mise.toml (lksdk requirement).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

internal/chat/chat.go

@@ -0,0 +1,177 @@
+// Package chat is the agent@ surface: talk to the operator's AI agent (or,
+// once the M2 admin console lands, the operator live).
+//
+// The agent backend is one configurable command, AGENTBBS_AGENT_CMD: each
+// user message is piped to its stdin, stdout comes back as the reply. Point
+// it at anything — `claude -p`, a logicsrc/commandboard agent, a shell
+// script. Unset = a polite "leave a message" mode (messages are persisted
+// either way, so the operator can read them later).
+package chat
+
+import (
+	"context"
+	"os"
+	"os/exec"
+	"strings"
+	"time"
+
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+	"github.com/charmbracelet/ssh"
+
+	"github.com/profullstack/agentbbs/internal/auth"
+	"github.com/profullstack/agentbbs/internal/store"
+)
+
+const historyLines = 200
+
+// Handle runs the chat UI; leaving ends the SSH session.
+func Handle(s ssh.Session, st store.Store, user auth.User) error {
+	ptyReq, winCh, hasPty := s.Pty()
+	if !hasPty {
+		_, _ = s.Write([]byte("agent chat needs a terminal (ssh -t)\r\n"))
+		return nil
+	}
+	m := &model{
+		st:     st,
+		user:   user,
+		width:  ptyReq.Window.Width,
+		height: ptyReq.Window.Height,
+	}
+	if msgs, err := st.RecentChats(user.Name, 20); err == nil {
+		for _, c := range msgs {
+			m.lines = append(m.lines, render(c.Role, c.Text))
+		}
+		if len(msgs) > 0 {
+			m.lines = append(m.lines, cDim.Render("— earlier conversation —"))
+		}
+	}
+	p := tea.NewProgram(m, tea.WithInput(s), tea.WithOutput(s), tea.WithAltScreen())
+	go func() {
+		for w := range winCh {
+			p.Send(tea.WindowSizeMsg{Width: w.Width, Height: w.Height})
+		}
+	}()
+	_, err := p.Run()
+	return err
+}
+
+var (
+	cTitle = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#c084fc"))
+	cYou   = lipgloss.NewStyle().Foreground(lipgloss.Color("#4ade80"))
+	cAgent = lipgloss.NewStyle().Foreground(lipgloss.Color("#c084fc"))
+	cDim   = lipgloss.NewStyle().Foreground(lipgloss.Color("241"))
+	cErr   = lipgloss.NewStyle().Foreground(lipgloss.Color("203"))
+)
+
+func render(role, text string) string {
+	if role == "user" {
+		return cYou.Render("you ") + text
+	}
+	return cAgent.Render("agent ") + text
+}
+
+type replyMsg struct {
+	text string
+	err  error
+}
+
+type model struct {
+	st   store.Store
+	user auth.User
+
+	lines   []string
+	input   string
+	waiting bool
+
+	width, height int
+}
+
+func (m *model) Init() tea.Cmd { return nil }
+
+// ask pipes the message to the configured agent command.
+func (m *model) ask(text string) tea.Cmd {
+	return func() tea.Msg {
+		cmdline := strings.TrimSpace(os.Getenv("AGENTBBS_AGENT_CMD"))
+		if cmdline == "" {
+			return replyMsg{text: "The operator's agent isn't wired up right now — your message is saved and a human will read it."}
+		}
+		ctx, cancel := context.WithTimeout(context.Background(), 120*time.Second)
+		defer cancel()
+		parts := strings.Fields(cmdline)
+		cmd := exec.CommandContext(ctx, parts[0], parts[1:]...)
+		cmd.Stdin = strings.NewReader(text)
+		out, err := cmd.Output()
+		if err != nil {
+			return replyMsg{err: err}
+		}
+		reply := strings.TrimSpace(string(out))
+		if reply == "" {
+			reply = "(no reply)"
+		}
+		return replyMsg{text: reply}
+	}
+}
+
+func (m *model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
+	switch msg := msg.(type) {
+	case tea.WindowSizeMsg:
+		m.width, m.height = msg.Width, msg.Height
+	case replyMsg:
+		m.waiting = false
+		if msg.err != nil {
+			m.lines = append(m.lines, cErr.Render("agent error: "+msg.err.Error()))
+			return m, nil
+		}
+		_ = m.st.AddChat(m.user.StoreID, m.user.Name, "agent", msg.text)
+		for _, l := range strings.Split(msg.text, "\n") {
+			m.lines = append(m.lines, render("agent", l))
+		}
+		if len(m.lines) > historyLines {
+			m.lines = m.lines[len(m.lines)-historyLines:]
+		}
+	case tea.KeyMsg:
+		switch msg.String() {
+		case "ctrl+c", "esc":
+			return m, tea.Quit
+		case "enter":
+			text := strings.TrimSpace(m.input)
+			if text == "" || m.waiting {
+				return m, nil
+			}
+			m.input = ""
+			m.waiting = true
+			_ = m.st.AddChat(m.user.StoreID, m.user.Name, "user", text)
+			m.lines = append(m.lines, render("user", text))
+			return m, m.ask(text)
+		case "backspace":
+			if len(m.input) > 0 {
+				m.input = m.input[:len(m.input)-1]
+			}
+		default:
+			if msg.Type == tea.KeyRunes || msg.String() == " " {
+				m.input += string(msg.Runes)
+			}
+		}
+	}
+	return m, nil
+}
+
+func (m *model) View() string {
+	rows := m.height - 4
+	if rows < 3 {
+		rows = 3
+	}
+	start := 0
+	if len(m.lines) > rows {
+		start = len(m.lines) - rows
+	}
+	body := strings.Join(m.lines[start:], "\n")
+	prompt := "> " + m.input + "█"
+	if m.waiting {
+		prompt = cDim.Render("agent is thinking…")
+	}
+	return lipgloss.NewStyle().Padding(0, 1).Render(
+		cTitle.Render("agent@ — talk to profullstack") + cDim.Render("  (esc to leave)") + "\n" +
+			body + "\n\n" + prompt)
+}