e2e fixes: tasks tool in profiles, bg timeout lift, stepIcon fix, queue semantics docs ...

E2E findings addressed:
- tasks tool was registered but not in any profile's tools.agent.native —
  added to all six profiles (agent could not check/wait/cancel bg tasks)
- detached terminal/code_exec/ssh_exec runs without explicit timeout are
  lifted to 300s: foreground defaults (20/30/60s) marked long commands
  'completed' with partial output while the process still ran
- ToolCard.vue: define stepIcon(status) — template referenced it but the
  function was missing (render crash on task_update step)
- message_queued reachability documented: WS read loop is sequential, the
  queue path is only reachable from a second socket/headless recall

agent parallelism: background tools, bg spawn_agent, parallel tool batches, message queue ...

- backgroundable tools (terminal/ssh_exec/peer/spawn_agent/code_exec) detach
  via TaskManager with per-session/global/spawn caps, rate limit and TTL
- completion delivery both ways: task_update event (out-of-band) + pending
  notes injected into the next turn; tasks tool (list/check/wait/cancel)
- parallel tool-call batches (profile-level gate, off by default) with
  ToolStarted up-front, tagged event mux, call-order results, one save,
  plus dangling tool_call repair on session load
- user message queue instead of busy error: message_queued frame,
  back-to-back drain on the same socket, headless fallback on disconnect
- pin mcp<2 (v2 renames FastMCP with breaking API changes)
- docs: tasks.md (new), websocket/api/agent/config updates, tasks manual,
  spawn_agent background param, persona contract section

persona: strengthen + duplicate the female-gender rule in Russian ...

The English one-liner was losing to the models' masculine default
(position at prompt head + weak signal). Now: a strict Russian rule
right after the intro and a short self-reminder at the very end of
persona.txt; same strengthening + reminder in persona_navi_code.txt.

Update Navi Code profile: config, prompts, docs, and env example ...

- Sync navi_code profile tools with current codebase (memory, schedule_recall, manage_recall, switch_profile, list_profiles)

- Remove image_view and MCP tools from navi_code; keep local terminal focus

- Update system prompt and persona for terminal-first coding assistant

- Update docs/navi_code.md, docs/profiles.md, docs/config.md for new tool set

- Refresh .env.navi_code.example with current config variables

- Remove stale CLI prototype directories (cli/, navi_code_cli/)

Navi Code: Phase 1 — terminal-first profile, default profile mechanism, env/persona, tests ...

- Add navi_code profile (terminal-first coding assistant)
- Add NAVI_DEFAULT_PROFILE_ID setting and POST /sessions default profile fallback
- Add persona_navi_code.txt and .env.navi_code.example
- Add docs/plan_navi_code.md phased plan
- Update tests to verify default-profile selection in no-auth mode

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