Code mode: card-backed Cloud trial gets the full Team experience (inline + cap 20) #1489

Follow-up to the per-plan gating (#1446 / PR #1447).

Today a Cloud free trial gets saved code tools (cap 3) but no inline code (code_execute / code_propose_tool are Team+). A trial that has added a card is a high-intent, low-abuse user (payment method on file), so it should experience the full product during the trial to drive conversion.

Change (gating policy only, no schema)

• A card-backed Cloud trial (license plan='trial' with billing.status='trialing') resolves to the Team experience for code mode: inline code allowed + saved-code-tool cap 20 (instead of 3).
• A free (card-less) trial is unchanged: tools-only, cap 3, no inline.
• Self-hosted is unaffected: its trial has no Stripe billing, so it stays tools-only.

Scope

• license/code-mode-quotas.ts: add effectiveCodeModePlan(plan, cardTrial) ('trial'+card -> 'team').
• license/license-guard.service.ts: resolve the effective plan (reading billing.status) in checkCanCreateCodeTool and canUseInlineCode.
• Tests + docs (code-mode.md 'Per plan' note) + regenerate llms.

No Prisma change. Cloud + self-hosted behaviour stated.