feat!: Drop support for Python 3.8 (eol 2024-10-07)

[devin-ai-integration]

Drop support for Python 3.8 (eol 2024-10-07)

Summary

This PR drops support for Python 3.8 across 6 LaunchDarkly Python repositories and adds support for Python 3.13, following the pattern established in launchdarkly/python-server-sdk.

Repositories updated:

• python-server-sdk-otel
• python-server-sdk-ai
• python-eventsource
• openfeature-python-server
• hello-python
• hello-openfeature-python-server

Key changes:

• Python version support: Minimum version bumped from 3.8 → 3.9, maximum extended to include 3.13
• Dependencies: Updated pyproject.toml classifiers and version constraints
• CI/CD: Updated GitHub Actions workflows to test Python 3.9-3.13 instead of 3.8-3.12
• Documentation: Updated README files to reflect new version support
• Special fixes: Upgraded Sphinx from ^1.3.0 to ^7.0.0 in python-eventsource to resolve Python 3.13 compatibility issues

Review & Testing Checklist for Human

• Verify Sphinx upgrade in python-eventsource: Test documentation generation locally with make docs to ensure the major Sphinx upgrade (1.3.0 → 7.0.0) doesn't break existing functionality
• Test runtime behavior on boundary versions: Install and run basic functionality tests on Python 3.9 (new minimum) and Python 3.13 (new maximum) to catch any runtime compatibility issues not covered by CI
• Confirm version bump strategy: Verify that the "Release-As" versions in commit messages follow the correct non-breaking version increments for each repository
• Spot-check for Python 3.8 remnants: Review any Python 3.8-specific code patterns or dependencies that might still exist in the codebases

---

Diagram

graph TD
    subgraph "Repository Changes"
        A[pyproject.toml]:::major-edit
        B[README.md]:::major-edit  
        C[.github/workflows/*.yml]:::major-edit
        D[Makefile]:::context
    end
    
    subgraph "python-eventsource Specific"
        E[pyproject.toml - Sphinx upgrade]:::major-edit
        F[poetry.lock - ignored by git]:::context
    end
    
    subgraph "hello-openfeature-python-server"
        G[pyproject.toml - package-mode fix]:::minor-edit
    end
    
    A --> |Removes Python 3.8 classifiers| H[Python 3.9-3.13 support]
    A --> |Updates python version constraint| H
    B --> |Documents new version support| H
    C --> |Updates CI test matrix| H
    E --> |Sphinx ^1.3.0 to ^7.0.0| I[Python 3.13 compatibility]
    
    subgraph Legend
        L1[Major Edit]:::major-edit
        L2[Minor Edit]:::minor-edit  
        L3[Context/No Edit]:::context
    end

classDef major-edit fill:#90EE90
classDef minor-edit fill:#87CEEB  
classDef context fill:#FFFFFF

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Notes

• Breaking change: This is a breaking change that drops support for Python 3.8, which reached end-of-life on 2024-10-07
• Sphinx compatibility: The python-eventsource repository required a major Sphinx upgrade due to Python 3.13 removing the pipes module that older Sphinx versions depended on
• CI validation: All 6 repositories now have passing CI checks across the new Python version matrix (3.9-3.13)
• Coordination: Changes follow the established pattern from python-server-sdk and maintain consistency across the LaunchDarkly Python ecosystem

Link to Devin run: https://app.devin.ai/sessions/3f70248c29dd4d5eb70be4a05a78ce3a
Requested by: @keelerm84

[devin-ai-integration]

Original prompt from mkeeler@launchdarkly.com:

SYSTEM:
=== BEGIN THREAD HISTORY (in #sdks-python) ===
GitHub (U01V5FFUQ1E): 

[launchdarkly/python-server-sdk] Pull request merged by keelerm84

Matthew Keeler (U02FZSQUVCL): <@U0915543DJ7> if you look at sha 02076650064d8a20f792c80cda3249a7aa7e336a from the python-server-sdk repository, you will see a commit where I've dropped python 3.8 support from one of our libraries. I also increased testing support up to 3.13.

I need you to make the same type of changes across multiple different repositories:

• <https://github.com/launchdarkly/python-server-sdk-otel>
• <https://github.com/launchdarkly/python-server-sdk-ai>
• <https://github.com/launchdarkly/python-eventsource>
• <https://github.com/launchdarkly/openfeature-python-server>
• <https://github.com/launchdarkly/hello-python>
• <https://github.com/launchdarkly/hello-openfeature-python-server>
For each of these repositories we want to make sure that:

1. We bump the minimum to 3.9.
2. Update the README to reflect this new minimum.
3. Update all github action files to no longer include 3.8.
4. Anywhere we list the versions of python that are supported, we should make sure to expand to include 3.13.
When working on the repositories, you should work under a branch named: mk/sdk-1351/3.8

The PR title should be similar to what you saw in the provided SHA. The commit body should also include a "Release-As: X.Y.Z" designation. That release number should be the next non-breaking version number. For example, if the last tag was 1.2.3, then this should be "Release-As: 1.3.0". Or if it's "0.3.0", it should be "Release-As: 0.4.0".

Matthew Keeler (U02FZSQUVCL): <@U0915543DJ7> see my last message and do that please.

Cursor (U0915543DJ7): <@U02FZSQUVCL> deleted "Update Python support across repositories"

<@U02FZSQUVCL> deleted "Update Python support across repositories"

Matthew Keeler (U02FZSQUVCL): <@U0915543DJ7> help

Cursor (U0915543DJ7): Welcome to Cursor for Slack! Here's how to use it:

Welcome! Here's how to use Cursor in Slack:


*Start an Agent*

Create a new agent to work on your task
```@Cursor [your task description]```

_Example:_ `@Cursor Fix the login bug we discussed in this thread`

:bulb: _Tip: Reply to an agent thread with @Cursor to add follow-up instructions_

*Agent Settings*

View and edit your default model, repository, and branch
```@Cursor settings```

Use a different model, repository, or branch for a single agent
```@Cursor [branch=dev, model=o3, repo=torvalds/linux] Fix the login bug```

*More Commands*


_Cursor agents run in the background and notify you when complete_

Matthew Keeler (U02FZSQUVCL): <@U0915543DJ7> list agents

Cursor (U0915543DJ7): Your Cursor Agents:
• <https://cursor.com/background-agent?bcId=bc-b630020f-dbf7-4666-b4d4-1105117b8f7b|Update Python support across repositories>

_Last 24 hours_

Cursor (U0915543DJ7): Background agent has successfully finished!

Background agent has successfully finished!

*Repository:* `launchdarkly/gonfalon`
*Branch:* `cursor/update-python-support-across-repositories-569b`

Matthew Keeler (U02FZSQUVCL): @Devin I’m sorry. I tried another AI bot but nothing can replace you. :heart: Can you read my first message in this thread and take a stab and doing all of that work? Thanks love!
=== END THREAD HISTORY ===

The latest message is the one right above that tagged you.

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