Add type hints to public APIs and configure mypy

- Improve mypy configuration with appropriate strictness settings
- Add comprehensive type hints to public API functions:
  - hookspecs.py: Type register_commands and prepare_connection hooks
  - plugins.py: Type get_plugins function and PluginManager
  - recipes.py: Type parsedate, parsedatetime, jsonsplit functions
  - utils.py: Type all public utility functions including rows_from_file,
    TypeTracker, ValueTracker, chunks, hash_record, flatten, etc.
  - db.py: Type Database, Queryable, Table, and View class methods
    including constructor, execute, query, table operations, etc.
- Exclude cli.py from strict checking (internal implementation detail)
- All public API modules now pass mypy type checking

sqlite_utils/plugins.py

@@ -1,8 +1,10 @@
+from typing import Any, Dict, List
+
 import pluggy
 import sys
 from . import hookspecs
 
-pm = pluggy.PluginManager("sqlite_utils")
+pm: pluggy.PluginManager = pluggy.PluginManager("sqlite_utils")
 pm.add_hookspecs(hookspecs)
 
 if not getattr(sys, "_called_from_test", False):
@@ -10,13 +12,14 @@ if not getattr(sys, "_called_from_test", False):
     pm.load_setuptools_entrypoints("sqlite_utils")
 
 
-def get_plugins():
-    plugins = []
+def get_plugins() -> List[Dict[str, Any]]:
+    plugins: List[Dict[str, Any]] = []
     plugin_to_distinfo = dict(pm.list_plugin_distinfo())
     for plugin in pm.get_plugins():
-        plugin_info = {
+        hookcallers = pm.get_hookcallers(plugin)
+        plugin_info: Dict[str, Any] = {
             "name": plugin.__name__,
-            "hooks": [h.name for h in pm.get_hookcallers(plugin)],
+            "hooks": [h.name for h in hookcallers] if hookcallers else [],
         }
         distinfo = plugin_to_distinfo.get(plugin)
         if distinfo: