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>

tests/gui/test_activation.py

@@ -152,21 +152,18 @@ class TestActivationFormSubmission:
         text = collected_text(home_app)
         assert "Data Cleaning Mastery" in text
 
-    def test_trial_button_self_issues_license(
-        self, no_license_env, home_app,
-    ):
+    def test_trial_button_absent_paid_only(self, no_license_env, home_app):
+        """v1.6 dropped the user-facing trial flow — paid licenses only.
+        Verify the trial button is not on the activation form."""
         home_app.run()
-        home_app.text_input(key="gate_name").set_value("Trial").run()
-        home_app.text_input(key="gate_email").set_value("trial@example.com").run()
-        # Click the trial button on the same form.
-        trial_btn = next(
-            b for b in home_app.button
-            if "trial" in b.label.lower() or "prueba" in b.label.lower()
-        )
-        trial_btn.click().run()
-        text = collected_text(home_app)
-        # Successful activation → home page renders fully.
-        assert "Data Cleaning Mastery" in text
+        labels = [b.label for b in home_app.button]
+        for lbl in labels:
+            assert "trial" not in lbl.lower(), (
+                f"trial button leaked into activation form: {lbl!r}"
+            )
+            assert "prueba" not in lbl.lower(), (
+                f"Spanish trial button leaked into form: {lbl!r}"
+            )
 
 
 class TestActivationPageDirect: