Loki Mode v7.44.0

Web-surface consolidation + local-ci parallelization. One local web surface (the
dashboard), Purple Lab deprecated with a value-preserving migration path, and the
dashboard gains browser PRD-input so nobody loses the ability to start a build
from a browser.

Changed

• Purple Lab (loki web, web-app/, port 57375) is DEPRECATED as of this release.
  Rationale: it was a second web surface (its own FastAPI server, auth, crypto,
  DB migrations) whose monitoring half duplicated the dashboard, whose advertised
  multi-user/account layer was unbacked UI, and whose hosted-platform role now
  lives in the separate Autonomi Cloud product. Consolidating to one local
  surface simplifies the UX and sharpens the open-core line (free CLI + local
  dashboard; paid hosted = Autonomi Cloud).
• loki web still works (value-preserving): it prints a deprecation banner
  pointing to the dashboard (auto-launches at loki start, http://localhost:57374,
  or loki dashboard) and to Autonomi Cloud for the hosted platform, emits a
  cli_command_deprecated telemetry event, then still launches Purple Lab so no
  existing user is stranded (mirrors the loki run -> loki start deprecation).

Added

• Dashboard can now START a build from the browser, absorbing Purple Lab's one
  unique value. New POST /api/control/start (scope: control) accepts a PRD as
  text or path (path-traversal guarded, post-resolution containment check),
  single-flight (409 if a run is already active), and spawns the run via run.sh.
  The SPA gains a spec textarea + a wired Start button (startSession in the API
  client). The dashboard is now the single local surface: monitor AND launch.
• local-ci parallelization re-land (#588): provably-independent read-only checks
  (bash -n, shellcheck, JSON/YAML/emoji/git-add structural, static-asset checks)
  run in concurrent background lanes; everything that spawns a process, hits the
  network (bun test), runs pytest, or shares mutable state (model-override,
  plan-command, the stop block) stays on a serial spine. A prior parallelization
  attempt was reverted for making the gate non-deterministic; this re-land was
  proven deterministic across 5 consecutive full runs (62 checks, 0 failures,
  identical each run). --serial / LOCAL_CI_SERIAL=1 is the bisect lever.

Docs

• README (Purple Lab section + nav link + commands table) and the Autonomi
  website (Docs product pages) repoint Purple Lab current-product framing to the
  dashboard (local) and Autonomi Cloud (hosted); historical changelog/launch
  artifacts left intact (deprecate with a pointer, never silently delete).