fix: restore dev features lost in main→dev merge
Merge b6f89f9 ('integrate main restructuring into dev') took main's
smaller refactored versions and overwrote dev-specific features.
Restored from dev commit 51a399c and ancestors:
Backend terminal (c754984, 37134b8):
- terminal_session.py: asyncio.add_reader event-driven I/O, flow control
(64KB pause/32KB resume), 2ms output batching, binary WebSocket frames,
EOF detection, circular replay buffer
- terminal_manager.py: named sessions, MaxSessionsExceededError,
TerminalSessionModel persistence, idle timeout cleanup
- terminal.py: dual WebSocket routes (/terminal and /terminal/{session_id}),
SessionRef mutable reference for session resets
SSH key mounting (c6b804b):
- instance_lifecycle.py: _mount_ssh_keys helper that prepares multiple
SSH keys with unique filenames (id_ed25519_<name>), writes combined
SSH config, mounts single ~/.ssh directory
- tool_instance.py: ssh_key_ids JSON column
- schemas/tool_instance.py: ssh_key_ids field in CreateInstanceRequest
- tool_instances.py: pass ssh_key_ids through create endpoint and response
Quality gates: py_compile passed, ruff passed on all edited files
alex
7ce2af18c9