Add tags prominence and SIM source grouping features

Database changes:
- Add sim_source_id column to artifacts table for grouping multiple artifacts
- Create Alembic migration (001_add_sim_source_id) for schema update
- Add Alembic env.py for migration support with environment-based DB URLs

API enhancements:
- Add sim_source_id parameter to upload endpoint
- Add sim_source_id filter to query endpoint
- Add new /grouped-by-sim-source endpoint for getting artifacts by group
- Update all API documentation to include sim_source_id

UI improvements:
- Make tags required field and more prominent in upload form
- Add tags display directly in artifacts table (below filename)
- Add SIM Source ID field in upload form with helper text for grouping
- Update table to show sim_source_id (falls back to test_suite if null)
- Tags now displayed as inline badges in main table view

Seed data updates:
- Generate sim_source_id for 70% of artifacts to demonstrate grouping
- Multiple artifacts can share same sim_source_id
- Improved seed data variety with tag combinations

Features:
- Tags are now prominently displayed in both table and detail views
- Multiple artifacts can be grouped by SIM source ID
- Users can filter/query by sim_source_id
- Backward compatible - existing artifacts without sim_source_id still work

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

alembic/env.py

@@ -0,0 +1,84 @@
+from logging.config import fileConfig
+import os
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+
+from alembic import context
+
+# Import your models Base
+from app.models.artifact import Base
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Override sqlalchemy.url from environment variable
+if os.getenv("DATABASE_URL"):
+    config.set_main_option("sqlalchemy.url", os.getenv("DATABASE_URL"))
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+target_metadata = Base.metadata
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+
+
+def run_migrations_offline() -> None:
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection, target_metadata=target_metadata
+        )
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()