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/provider/session/sessionmgr.py

@@ -0,0 +1,75 @@
+from __future__ import annotations
+
+import asyncio
+
+from ...core import app
+from langbot_plugin.api.entities.builtin.provider import message as provider_message, prompt as provider_prompt
+import langbot_plugin.api.entities.builtin.provider.session as provider_session
+import langbot_plugin.api.entities.builtin.pipeline.query as pipeline_query
+
+
+class SessionManager:
+    """会话管理器"""
+
+    ap: app.Application
+
+    session_list: list[provider_session.Session]
+
+    def __init__(self, ap: app.Application):
+        self.ap = ap
+        self.session_list = []
+
+    async def initialize(self):
+        pass
+
+    async def get_session(self, query: pipeline_query.Query) -> provider_session.Session:
+        """获取会话"""
+        for session in self.session_list:
+            if query.launcher_type == session.launcher_type and query.launcher_id == session.launcher_id:
+                return session
+
+        session_concurrency = self.ap.instance_config.data['concurrency']['session']
+
+        session = provider_session.Session(
+            launcher_type=query.launcher_type,
+            launcher_id=query.launcher_id,
+        )
+        session._semaphore = asyncio.Semaphore(session_concurrency)
+        self.session_list.append(session)
+        return session
+
+    async def get_conversation(
+        self,
+        query: pipeline_query.Query,
+        session: provider_session.Session,
+        prompt_config: list[dict],
+        pipeline_uuid: str,
+        bot_uuid: str,
+    ) -> provider_session.Conversation:
+        """获取对话或创建对话"""
+
+        if not session.conversations:
+            session.conversations = []
+
+        # set prompt
+        prompt_messages = []
+
+        for prompt_message in prompt_config:
+            prompt_messages.append(provider_message.Message(**prompt_message))
+
+        prompt = provider_prompt.Prompt(
+            name='default',
+            messages=prompt_messages,
+        )
+
+        if session.using_conversation is None or session.using_conversation.pipeline_uuid != pipeline_uuid:
+            conversation = provider_session.Conversation(
+                prompt=prompt,
+                messages=[],
+                pipeline_uuid=pipeline_uuid,
+                bot_uuid=bot_uuid,
+            )
+            session.conversations.append(conversation)
+            session.using_conversation = conversation
+
+        return session.using_conversation