feat!: adopt Python 3.14 and 3.15 language features

- Require Python 3.15 for the server and Python 3.14 for the CLI.
- Match the server requirement to quart_common's Python 3.15 features.
- Replace future annotations with native deferred evaluation.
- Defer CLI command dependencies and QR imports on Python 3.15.
- Enable argparse suggestions for mistyped CLI commands.
- Remove the obsolete tomllib import fallback.
- Update my_helpers and quart_common submodule references.
- Lock test dependencies and exclude them from Docker installations.
- Add regression coverage for lazy imports and deferred annotations.
- Document runtime requirements and standalone CLI validation.
- Validate 276 tests on Python 3.15 and 18 CLI tests on Python 3.14.

BREAKING CHANGE: The server now requires Python 3.15+ and the standalone CLI requires Python 3.14+.

cli/nanoshare_client/__main__.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 import sys
 
 from .cli import main

cli/nanoshare_client/app.py

@@ -1,13 +1,8 @@
-from __future__ import annotations
-
 import os
 import sys
 from pathlib import Path
 
-try:
-  import tomllib
-except ImportError:  # pragma: no cover
-  tomllib = None
+import tomllib
 
 from .config import DEFAULT_CONFIG
 from .http_client import NanoShareClient
@@ -24,7 +19,7 @@ def parse_registry_env(value: str) -> dict[str, str]:
   return registry
 
 def load_config(path: str | os.PathLike | None) -> dict:
-  if not path or tomllib is None:
+  if not path:
     return {}
   config_path = Path(path).expanduser()
   if not config_path.is_file():

cli/nanoshare_client/auth.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 import secrets
 import threading
 import webbrowser

cli/nanoshare_client/cli.py

@@ -1,4 +1,13 @@
-from __future__ import annotations
+# Python 3.15 defers command-specific imports; 3.14 imports them normally.
+__lazy_modules__ = [
+  "nanoshare_client.app",
+  "nanoshare_client.auth",
+  "nanoshare_client.client",
+  "nanoshare_client.completion",
+  "nanoshare_client.sync",
+  "nanoshare_client.table",
+  "nanoshare_client.watch",
+]
 
 import argparse
 import json
@@ -120,7 +129,11 @@ def _add_common(parser: argparse.ArgumentParser) -> None:
   parser.add_argument('--node', default=DEFAULT_NODE, help='NanoShare node name.')
 
 def main(argv: list[str] | None = None) -> int:
-  parser = argparse.ArgumentParser(prog='nanoshare', description='NanoShare CLI and folder sync client.')
+  parser = argparse.ArgumentParser(
+    prog='nanoshare',
+    description='NanoShare CLI and folder sync client.',
+    suggest_on_error=True,
+  )
   sub = parser.add_subparsers(dest='command', required=True)
 
   login = sub.add_parser('login', help='Login via browser and write CLI config.')

cli/nanoshare_client/client.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 import base64
 import mimetypes
 from pathlib import Path

cli/nanoshare_client/completion.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 _ZSH = r'''# nanoshare zsh completion -- add to ~/.zshrc:  eval "$(nanoshare completion zsh)"
 _nanoshare_files() {
   local id path name size label

cli/nanoshare_client/config.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 from pathlib import Path
 
 DEFAULT_CONFIG = Path('~/.config/nanoshare/config.toml').expanduser()

cli/nanoshare_client/envelope.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 import time
 import uuid
 

cli/nanoshare_client/http_client.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 import hashlib
 import json
 import os

cli/nanoshare_client/ignore.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 from fnmatch import fnmatch
 from pathlib import Path
 

cli/nanoshare_client/remote_path.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 from pathlib import PurePosixPath
 
 def split_remote_path(value: str, file_id: str = '') -> tuple[str, str]:

cli/nanoshare_client/sync.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 import hashlib
 import json
 import os

cli/nanoshare_client/table.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 from collections.abc import Iterable
 
 def _display_width(value: str) -> int:

cli/nanoshare_client/watch.py

@@ -1,5 +1,3 @@
-from __future__ import annotations
-
 import sys
 import threading
 import time

cli/pyproject.toml

@@ -3,7 +3,7 @@ name = "nanoshare-cli"
 version = "0.4.2"
 description = "NanoShare desktop CLI and folder sync client"
 readme = "README.md"
-requires-python = ">=3.11"
+requires-python = ">=3.14"
 dependencies = [
   "httpx==0.28.1",
   "watchdog==6.0.0",