feat(license): add Lite SKU; remove user-facing free trial

Two coupled changes:

1. Lite tier
   - New Tier.LITE in src/license/schema.py.
   - FEATURES_BY_TIER[Tier.LITE] = {Deduplicator, Text Cleaner,
     Format Standardizer}. The three universally-useful tools that
     cover the most common bookkeeping / RevOps / Klaviyo prep
     workflows. Other six tools require Core.
   - i18n: license.tier_lite, license.feature_locked_title,
     license.feature_locked_body, license.upgrade_link,
     license.status_locked (en + es).
   - Per-tool feature gate at every GUI tool page
     (require_feature_or_render_upgrade) and every tool CLI
     (guard(feature=...)). A locked tool renders an upgrade
     prompt + Manage-license button (GUI) or exits with code 2
     (CLI).
   - Home grid: tool cards the user's tier doesn't unlock get a
     red 🔒 Locked badge in place of green Ready.

2. Trial removed
   - Activation form's "Start 1-year trial" button removed.
   - license_cli's `trial` subcommand removed.
   - activation.trial_button / activation.trial_help i18n keys
     dropped (pack parity test stays green).
   - Tier.TRIAL stays in the enum (back-compat with any field-
     tested trial licenses); LicenseManager._mint stays internal
     for tests and the seller's key generator.
   - Decision logged in DECISIONS §9b: a 1-year all-features
     trial undercuts paid Lite; paid-only keeps tier economics
     clean.

Tests (+29 net): +17 Lite-tier unit/guard tests + 13 Lite-tier
GUI tests + 1 trial-absent assertion - 2 trial CLI tests - 1
trial GUI button test. Total: 1995 → 2024.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/i18n/packs/en.json

@@ -68,8 +68,6 @@
     "blob_help": "Begins with `DTLIC1:` — paste the entire string.",
     "activate_button": "Activate",
     "renew_button": "Apply renewal",
-    "trial_button": "Start 1-year trial",
-    "trial_help": "Skips the paid blob and self-issues a 1-year license tied to your name and email. Useful for evaluating before purchase.",
     "or_separator": "— or —",
     "success": "Activated! Welcome, {name}. Your license is valid until {expires}.",
     "renewed": "License renewed. New expiry: {expires}.",
@@ -86,13 +84,18 @@
     "renewal_warning_30": "⚠️ License expires in {days} days. Renew soon to avoid interruption.",
     "renewal_warning_expired": "🛑 License expired on {date}. Renew to continue using DataTools.",
     "tier_trial": "Trial",
+    "tier_lite": "Lite",
     "tier_core": "Core",
     "tier_pro": "Pro",
     "tier_enterprise": "Enterprise",
     "registered_to": "Registered to {name} · {email}",
     "expires_on": "Expires on {date}",
     "issued_on": "Issued on {date}",
-    "view_details": "License details"
+    "view_details": "License details",
+    "feature_locked_title": "🔒 This tool isn't on your {tier} license",
+    "feature_locked_body": "Your current license unlocks: {features}. Upgrade to access this tool.",
+    "upgrade_link": "Manage license",
+    "status_locked": "Locked"
   },
   "tools": {
     "01_deduplicator": {