feat: implement user data schema and API endpoints

- Add Alembic migration setup with async configuration
- Create 16 user data models (users, decks, cards, replays, etc.)
- Implement comprehensive API endpoints with JWT auth
- Add replay, card collection, group, network, preferences, and activity log routers
- Include API documentation and migration test plan
- Update Dockerfile to run migrations on startup

backend/alembic.ini

@@ -0,0 +1,86 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = alembic
+
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+# see https://alembic.sqlalchemy.org/en/latest/tutorial.html#editing-the-ini-file
+# for all available tokens
+# file_template = %%(year)d_%%(month).2d_%%(day).2d_%%(hour).2d%%(minute).2d-%%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.
+prepend_sys_path = .
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the python>=3.9 or python-dateutil library.
+# https://alembic.sqlalchemy.org/en/latest/cookbook.html#using-the-_new_tzinfo_techique_to_run_in_a_specific_timezone
+# timezone =
+
+# max length of characters to apply to the "slug" field
+# truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a .py source will be used as the source for the executed
+# .py source files.
+# sourceless = false
+
+# version location specification; This defaults
+# to alembic/versions. When using multiple version
+# directories, initial revisions must be specified with --start-version.
+# version_path_separator = os
+
+# output encoding. If set to utf-8, it will encode all output for utf-8 encoding.
+# If set to utf-8-sig, the BOM will be written to the output.
+# This is useful for files that will be opened in Windows editors.
+output_encoding = utf-8
+
+sqlalchemy.url = postgresql+asyncpg://mtgonline_user:mtgonline_password@postgres:5432/mtgonline
+
+
+[post_write_hooks]
+# post_write_hooks defines scripts or Python functions that are run
+# on newly generated revision scripts. See https://alembic.sqlalchemy.org/en/latest/hooks.html
+# for hooks documentation.
+
+# Logging configuration
+[loggers]
+keys = root, sqlalchemy, alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARN
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S