feat: add user subscription info endpoints

New router: routers/subscription.py
Endpoints:
- GET /api/subscription/me - Own subscription info (tier, trial, grants)
- GET /api/subscription/usage - Feature usage with limits
- GET /api/subscription/limits - All feature limits for current tier

Features:
- Shows effective tier (considers access_grants)
- Lists active access grants (from coupons, trials)
- Per-feature usage tracking
- Email verification status

Uses new middleware: get_effective_tier(), check_feature_access()

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/main.py

@@ -17,7 +17,7 @@ from db import init_db
 # Import routers
 from routers import auth, profiles, weight, circumference, caliper
 from routers import activity, nutrition, photos, insights, prompts
-from routers import admin, stats, exportdata, importdata
+from routers import admin, stats, exportdata, importdata, subscription
 
 # ── App Configuration ─────────────────────────────────────────────────────────
 DATA_DIR   = Path(os.getenv("DATA_DIR",   "./data"))
@@ -73,6 +73,7 @@ app.include_router(admin.router)          # /api/admin/*
 app.include_router(stats.router)          # /api/stats
 app.include_router(exportdata.router)     # /api/export/*
 app.include_router(importdata.router)     # /api/import/*
+app.include_router(subscription.router)   # /api/subscription/*
 
 # ── Health Check ──────────────────────────────────────────────────────────────
 @app.get("/")

backend/routers/subscription.py

@@ -0,0 +1,187 @@
+"""
+User Subscription Endpoints for Mitai Jinkendo
+
+User-facing subscription info (own tier, usage, limits).
+"""
+from datetime import datetime
+from fastapi import APIRouter, Depends
+
+from db import get_db, get_cursor, r2d
+from auth import require_auth, get_effective_tier, check_feature_access
+
+router = APIRouter(prefix="/api/subscription", tags=["subscription"])
+
+
+@router.get("/me")
+def get_my_subscription(session: dict = Depends(require_auth)):
+    """
+    Get current user's subscription info.
+
+    Returns:
+        - tier: Current effective tier (considers access_grants)
+        - profile_tier: Base tier from profile
+        - trial_ends_at: Trial expiration (if applicable)
+        - email_verified: Email verification status
+        - active_grants: List of active access grants (coupons, trials)
+    """
+    profile_id = session['profile_id']
+
+    with get_db() as conn:
+        cur = get_cursor(conn)
+
+        # Get profile info
+        cur.execute("""
+            SELECT tier, trial_ends_at, email_verified
+            FROM profiles
+            WHERE id = %s
+        """, (profile_id,))
+        profile = cur.fetchone()
+
+        if not profile:
+            return {"error": "Profile not found"}
+
+        # Get effective tier (considers access_grants)
+        effective_tier = get_effective_tier(profile_id)
+
+        # Get active access grants
+        cur.execute("""
+            SELECT
+                ag.id,
+                ag.tier_id,
+                ag.granted_by,
+                ag.valid_from,
+                ag.valid_until,
+                ag.is_active,
+                ag.paused_by,
+                ag.remaining_days,
+                t.name as tier_name
+            FROM access_grants ag
+            JOIN tiers t ON t.id = ag.tier_id
+            WHERE ag.profile_id = %s
+              AND ag.valid_until > CURRENT_TIMESTAMP
+            ORDER BY ag.valid_until DESC
+        """, (profile_id,))
+        grants = [r2d(r) for r in cur.fetchall()]
+
+        # Get tier info
+        cur.execute("""
+            SELECT id, name, description, price_monthly_cents, price_yearly_cents
+            FROM tiers
+            WHERE id = %s
+        """, (effective_tier,))
+        tier_info = r2d(cur.fetchone())
+
+        return {
+            "tier": effective_tier,
+            "tier_info": tier_info,
+            "profile_tier": profile['tier'],
+            "trial_ends_at": profile['trial_ends_at'].isoformat() if profile['trial_ends_at'] else None,
+            "email_verified": profile['email_verified'],
+            "active_grants": grants
+        }
+
+
+@router.get("/usage")
+def get_my_usage(session: dict = Depends(require_auth)):
+    """
+    Get current user's feature usage.
+
+    Returns list of features with current usage and limits.
+    """
+    profile_id = session['profile_id']
+
+    with get_db() as conn:
+        cur = get_cursor(conn)
+
+        # Get all active features
+        cur.execute("""
+            SELECT id, name, category, limit_type, reset_period
+            FROM features
+            WHERE active = true
+            ORDER BY category, name
+        """)
+        features = [r2d(r) for r in cur.fetchall()]
+
+        # Get usage for each feature
+        usage_list = []
+        for feature in features:
+            access = check_feature_access(profile_id, feature['id'])
+            usage_list.append({
+                "feature_id": feature['id'],
+                "feature_name": feature['name'],
+                "category": feature['category'],
+                "limit_type": feature['limit_type'],
+                "reset_period": feature['reset_period'],
+                "allowed": access['allowed'],
+                "limit": access['limit'],
+                "used": access['used'],
+                "remaining": access['remaining'],
+                "reason": access['reason']
+            })
+
+        return {
+            "tier": get_effective_tier(profile_id),
+            "features": usage_list
+        }
+
+
+@router.get("/limits")
+def get_my_limits(session: dict = Depends(require_auth)):
+    """
+    Get all feature limits for current tier.
+
+    Simplified view - just shows what's allowed/not allowed.
+    """
+    profile_id = session['profile_id']
+    tier_id = get_effective_tier(profile_id)
+
+    with get_db() as conn:
+        cur = get_cursor(conn)
+
+        # Get all features with their limits for this tier
+        cur.execute("""
+            SELECT
+                f.id,
+                f.name,
+                f.category,
+                f.limit_type,
+                COALESCE(tl.limit_value, f.default_limit) as limit_value
+            FROM features f
+            LEFT JOIN tier_limits tl ON tl.feature_id = f.id AND tl.tier_id = %s
+            WHERE f.active = true
+            ORDER BY f.category, f.name
+        """, (tier_id,))
+
+        features = []
+        for row in cur.fetchall():
+            rd = r2d(row)
+            limit = rd['limit_value']
+
+            # Interpret limit
+            if limit is None:
+                status = "unlimited"
+            elif limit == 0:
+                status = "disabled"
+            elif rd['limit_type'] == 'boolean':
+                status = "enabled" if limit == 1 else "disabled"
+            else:
+                status = f"limit: {limit}"
+
+            features.append({
+                "feature_id": rd['id'],
+                "feature_name": rd['name'],
+                "category": rd['category'],
+                "limit": limit,
+                "status": status
+            })
+
+        # Get tier info
+        cur.execute("SELECT name, description FROM tiers WHERE id = %s", (tier_id,))
+        tier = cur.fetchone()
+
+        return {
+            "tier_id": tier_id,
+            "tier_name": tier['name'] if tier else tier_id,
+            "tier_description": tier['description'] if tier else '',
+            "features": features
+        }