feat: replace wk1/wk4 targets with 6→8→10→12 rep ladder progression

Simplifies the progression model to a universal rep ladder: every exercise
follows 6→8→10→12 reps at current weight, then +5 lbs and reset to 6.
Replaces per-user wk1/wk4 rep and weight targets with a single
starting_weight field.

- Add Alembic migration to drop wk1_reps/wk4_reps/wk1_weight/wk4_weight,
  add starting_weight (migrated from wk1_weight)
- Run Alembic migrations on app startup instead of create_all, with
  auto-detection and stamping for legacy databases
- Include alembic/ and alembic.ini in Docker image
- Rewrite progression_service.get_suggestion() with ladder logic:
  climb, hold, weight_increase, hold_at_top, deload
- Replace wk1/wk4 grid in exercise cards with rep ladder progress bar
- Add color-coded progression badges by type
- Change weight log input from text to number with pre-filled suggestion
- Normalize weight input in routes (0→BW, bare number→N lbs)
- Remove schedule page (route, template, nav link, tests)
- Simplify user_programs.yaml from 4 fields to 1 per exercise
- Update all tests for new schema and progression logic

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

app/main.py

@@ -7,10 +7,12 @@ static files, and structured logging.
 from pathlib import Path
 
 import structlog
+from alembic import command as alembic_command
+from alembic.config import Config as AlembicConfig
 from fastapi import FastAPI
 from fastapi.staticfiles import StaticFiles
 from fastapi.templating import Jinja2Templates
-from sqlmodel import SQLModel, Session
+from sqlmodel import Session
 
 from starlette.middleware.base import BaseHTTPMiddleware, RequestResponseEndpoint
 from starlette.requests import Request as StarletteRequest
@@ -29,7 +31,6 @@ from app.routes.profiles import router as profiles_router
 from app.routes.logging import router as logging_router
 from app.routes.workouts import router as workouts_router
 from app.routes.dashboard import router as dashboard_router
-from app.routes.schedule import router as schedule_router
 from app.services.seed_service import SeedService
 from app.services.user_service import UserService
 from app.utils.auth import NoProfileSelectedError
@@ -64,6 +65,50 @@ class NavContextMiddleware(BaseHTTPMiddleware):
         return await call_next(request)
 
 
+def _run_migrations(database_url: str) -> None:
+    """Run Alembic migrations to bring the DB schema up to date.
+
+    On a fresh DB this creates all tables via the initial migration.
+    On an existing DB created by create_all (no alembic_version table),
+    stamps the last known pre-migration revision, then upgrades.
+    """
+    from sqlalchemy import create_engine as sa_create_engine, inspect
+
+    project_root = Path(__file__).resolve().parent.parent
+    alembic_cfg = AlembicConfig(str(project_root / "alembic.ini"))
+    alembic_cfg.set_main_option("script_location", str(project_root / "alembic"))
+    alembic_cfg.set_main_option("sqlalchemy.url", database_url)
+
+    engine = sa_create_engine(database_url)
+    inspector = inspect(engine)
+    existing_tables = inspector.get_table_names()
+
+    if existing_tables and "alembic_version" not in existing_tables:
+        # DB was created by create_all — stamp it at the last revision
+        # that matches the current schema so migrations run from there.
+        # Check which schema state we're in by looking at columns.
+        columns = {c["name"] for c in inspector.get_columns("user_exercise_programs")}
+        if "wk1_reps" in columns:
+            # Old schema: stamp at remove-auth migration (before rep ladder)
+            alembic_command.stamp(alembic_cfg, "a1b2c3d4e5f6")
+            logger.info("alembic_stamped", revision="a1b2c3d4e5f6", reason="legacy_db_old_schema")
+        elif "starting_weight" in columns:
+            # New schema already: stamp at head
+            alembic_command.stamp(alembic_cfg, "head")
+            logger.info("alembic_stamped", revision="head", reason="legacy_db_new_schema")
+        else:
+            # Unknown state — stamp at initial and let migrations sort it out
+            alembic_command.stamp(alembic_cfg, "1855836abf6c")
+            logger.info("alembic_stamped", revision="1855836abf6c", reason="legacy_db_unknown")
+    elif not existing_tables:
+        # Fresh DB — create alembic_version table so upgrade starts from scratch
+        logger.info("fresh_database_detected")
+
+    engine.dispose()
+    alembic_command.upgrade(alembic_cfg, "head")
+    logger.info("migrations_applied")
+
+
 def create_app() -> FastAPI:
     """Create and configure the FastAPI application.
 
@@ -103,11 +148,10 @@ def create_app() -> FastAPI:
     app.include_router(profiles_router)
     app.include_router(workouts_router)
     app.include_router(dashboard_router)
-    app.include_router(schedule_router)
 
-    # Database setup
+    # Database setup — run Alembic migrations instead of create_all
     engine = get_engine(settings.database_url)
-    SQLModel.metadata.create_all(engine)
+    _run_migrations(settings.database_url)
     app.state.engine = engine
 
     # DB session dependency for routes