Aura Widget Draft Persistence

Reviewer's assessment

SPEC FIDELITY
- Implemented: Draft text and attached screenshot state are persisted to sessionStorage with an org-scoped key, restored on widget re-mount/open, and intentionally not wiped on close. Upon successful submission the input/screenshot state resets, which triggers clearing the stored draft. Tests cover: typing persists, restore-on-open, screenshot restore, clear on submit, keep on close. This matches the approved spec.
- Slightly extra but consistent: visionContext is also persisted/restored to keep screenshot context in sync. This is a reasonable adjunct to “attached screenshots” and doesn’t introduce scope creep in behavior.
- Out-of-scope changes: Marketing API/page added guards for missing env vars and default responses. These are unrelated to the feature and constitute minor scope creep, though they are low-risk.

SECURITY
- sessionStorage is same-origin, ephemeral to the browser session, and suitable for this use case. No secrets or tokens are stored; only user-entered draft text and screenshot URL/context.
- Draft keys are namespaced by orgId, avoiding cross-org bleed.
- No relaxation of auth/RLS. Supabase service-role usage in marketing routes/pages remains as before; only guards were added when env vars are absent.

DESTRUCTIVENESS
- Widget close no longer clears input/screenshot/visionContext, by design per spec. Other state is still reset. No data/schema changes. No unrelated deletions.
- Marketing guard changes alter behavior only when env vars are missing (returning null/zeros). This could mask misconfiguration in non-local environments but is not destructive.

WHY SAFE/FAITHFUL
- Behavior aligns exactly with the spec: persistence limited to the browser session via sessionStorage; auto-restore; cleared on submit/session end. Tests exercise the critical paths. No secrets exposed, and changes are localized to the widget plus harmless env guards elsewhere.