Add fastmcp generate-cli command (#3065)

* Add `fastmcp generate-cli` command

Connects to any MCP server, reads its tool/resource/prompt schemas,
and writes a standalone Python CLI script with typed subcommands.

* docs: add generate-cli documentation

* docs: add generate-cli documentation; skip Windows executable test

* fix: address PR review feedback

- Sanitize tool and parameter names to valid Python identifiers
- Replace bare except Exception with specific exception types
- Escape server name in generated string literals
- Handle trailing colon edge case in _derive_server_name
- Clarify in docs that generated CLI is a client, not a bundled server

* Fix string escaping issues in generate-cli

- Use single-quoted docstrings to avoid triple-quote escaping issues
- Escape quotes in app_name derived from server_name
- Add tests for descriptions with quotes and server names with quotes

Addresses CodeRabbit review comments about insufficient escaping.

* Implement smart parameter handling for generate-cli

- Simple types (str, int, float, bool): Direct typed flags
- Arrays of simple types (list[str], list[int]): Repeatable flags via cyclopts
- Complex types (objects, nested arrays): Accept JSON strings with parsing
- JSON schema shown in help text for complex parameters
- Proper escaping of newlines and quotes in help text
- Filter out None and empty list defaults when calling tools

This gives typed, discoverable CLIs for common cases while handling
complex schemas via JSON input.

* Update generate-cli docs to explain smart parameter handling

- Document simple types as direct typed flags
- Document arrays of simple types as repeatable flags
- Document complex types as JSON strings with schema in help
- Add examples showing all three patterns

* Fix Codex review issues in generate-cli

High priority fixes:
- Complex type defaults: Serialize dict/list defaults to JSON strings
- List params: Preserve help metadata with Annotated wrapper
- Name collisions: Detect and error on sanitized name conflicts
- JSON parsing: Use isinstance check for safety with defaults

Added tests for:
- Complex types with default values
- Parameter name collision detection
- Updated existing tests to match new format

* Use pydantic_core.to_json for consistency

- Generator now uses pydantic_core.to_json() instead of json.dumps()
- Consistent with rest of fastmcp codebase
- Generated CLI still uses plain json module (standalone script)

* Move local imports to module level in generate-cli

* Handle union item types and Python keyword collisions in generate-cli

docs/docs.json

@@ -169,6 +169,7 @@
                 "pages": [
                   "clients/client",
                   "clients/cli",
+                  "clients/generate-cli",
                   "clients/transports",
                   {
                     "group": "Core Operations",