chore: Add PyPI package support for uvx/pip installation (#1764)

* Initial plan

* Add package structure and resource path utilities

- Created langbot/ package with __init__.py and __main__.py entry point
- Added paths utility to find frontend and resource files from package installation
- Updated config loading to use resource paths
- Updated frontend serving to use resource paths
- Added MANIFEST.in for package data inclusion
- Updated pyproject.toml with build system and entry points

Co-authored-by: RockChinQ <45992437+RockChinQ@users.noreply.github.com>

* Add PyPI publishing workflow and update license

- Created GitHub Actions workflow to build frontend and publish to PyPI
- Added license field to pyproject.toml to fix deprecation warning
- Updated .gitignore to exclude build artifacts
- Tested package building successfully

Co-authored-by: RockChinQ <45992437+RockChinQ@users.noreply.github.com>

* Add PyPI installation documentation

- Created PYPI_INSTALLATION.md with detailed installation and usage instructions
- Updated README.md to feature uvx/pip installation as recommended method
- Updated README_EN.md with same changes for English documentation

Co-authored-by: RockChinQ <45992437+RockChinQ@users.noreply.github.com>

* Address code review feedback

- Made package-data configuration more specific to langbot package only
- Improved path detection with caching to avoid repeated file I/O
- Removed sys.path searching which was incorrect for package data
- Removed interactive input() call for non-interactive environment compatibility
- Simplified error messages for version check

Co-authored-by: RockChinQ <45992437+RockChinQ@users.noreply.github.com>

* Fix code review issues

- Use specific exception types instead of bare except
- Fix misleading comments about directory levels
- Remove redundant existence check before makedirs with exist_ok=True
- Use context manager for file opening to ensure proper cleanup

Co-authored-by: RockChinQ <45992437+RockChinQ@users.noreply.github.com>

* Simplify package configuration and document behavioral differences

- Removed redundant package-data configuration, relying on MANIFEST.in
- Added documentation about behavioral differences between package and source installation
- Clarified that include-package-data=true uses MANIFEST.in for data files

Co-authored-by: RockChinQ <45992437+RockChinQ@users.noreply.github.com>

* chore: update pyproject.toml

* chore: try pack templates in langbot/

* chore: update

* chore: update

* chore: update

* chore: update

* chore: update

* chore: adjust dir structure

* chore: fix imports

* fix: read default-pipeline-config.json

* fix: read default-pipeline-config.json

* fix: tests

* ci: publish pypi

* chore: bump version 4.6.0-beta.1 for testing

* chore: add templates/**

* fix: send adapters and requesters icons

* chore: bump version 4.6.0b2 for testing

* chore: add platform field for docker-compose.yaml

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: RockChinQ <45992437+RockChinQ@users.noreply.github.com>
Co-authored-by: Junyan Qin <rockchinq@gmail.com>

src/langbot/pkg/core/notes/n001_classic_msgs.py

@@ -0,0 +1,16 @@
+from __future__ import annotations
+
+import typing
+
+from .. import note
+
+
+@note.note_class('ClassicNotes', 1)
+class ClassicNotes(note.LaunchNote):
+    """Classic launch information"""
+
+    async def need_show(self) -> bool:
+        return True
+
+    async def yield_note(self) -> typing.AsyncGenerator[typing.Tuple[str, int], None]:
+        yield await self.ap.ver_mgr.show_version_update()

src/langbot/pkg/core/notes/n002_selection_mode_on_windows.py

@@ -0,0 +1,26 @@
+from __future__ import annotations
+
+import typing
+import os
+import logging
+
+from .. import note
+
+
+@note.note_class('SelectionModeOnWindows', 2)
+class SelectionModeOnWindows(note.LaunchNote):
+    """Selection mode prompt information on Windows"""
+
+    async def need_show(self) -> bool:
+        return os.name == 'nt'
+
+    async def yield_note(self) -> typing.AsyncGenerator[typing.Tuple[str, int], None]:
+        yield (
+            """您正在使用 Windows 系统，若窗口左上角显示处于”选择“模式，程序将被暂停运行，此时请右键窗口中空白区域退出选择模式。""",
+            logging.INFO,
+        )
+
+        yield (
+            """You are using Windows system, if the top left corner of the window displays "Selection" mode, the program will be paused running, please right-click on the blank area in the window to exit the selection mode.""",
+            logging.INFO,
+        )

src/langbot/pkg/core/notes/n003_print_version.py

@@ -0,0 +1,17 @@
+from __future__ import annotations
+
+import typing
+import logging
+
+from .. import note
+
+
+@note.note_class('PrintVersion', 3)
+class PrintVersion(note.LaunchNote):
+    """Print Version Information"""
+
+    async def need_show(self) -> bool:
+        return True
+
+    async def yield_note(self) -> typing.AsyncGenerator[typing.Tuple[str, int], None]:
+        yield f'Current Version: {self.ap.ver_mgr.get_current_version()}', logging.INFO