chore: align Python release publishing with Ruby

[marandaneto]

💡 Motivation and Context

Align the split Python release workflow with the Ruby release workflow so publish-time tag creation uses the checkout credentials instead of an explicit GH_TOKEN, while keeping gh release create authenticated with ${{ github.token }} like Ruby.

The publish job now configures git, fetches tags, skips package releases when the expected tag already exists, creates annotated tags with git, and creates GitHub releases from a generated release-notes.md file. The release-notes extraction preserves the fallback text when the latest changelog section is missing or empty.

The root CHANGELOG.md now mirrors Ruby's package index pattern and points to the package-specific changelogs. The historical posthog changelog moved to posthog/CHANGELOG.md, and the release workflow copies it into the root only while running sampo release, then moves the generated changelog back to posthog/CHANGELOG.md and restores the root index.

RELEASING.md is updated to document all published packages, package-specific changelog locations, and package-prefixed release tags.

This also includes a patch changeset for both posthog and openfeature-provider-posthog so the updated release flow can be exercised after merge.

💚 How did you test it?

• Parsed .github/workflows/release.yml with PyYAML.
• Tested the release-notes extraction locally with populated, empty, and missing-section changelog cases.
• Simulated the sampo release changelog relocation flow in a temporary clone with a temporary changeset and confirmed the root changelog stays as an index while posthog/CHANGELOG.md receives the generated entry.
• Ran SAMPO_RELEASE_BRANCH=main sampo release --dry-run with the committed changeset and confirmed planned patch releases for both packages.
• Ran git diff --check.

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• I updated the docs if needed.
• No breaking change or entry added to the changelog.

If releasing new changes

• Ran sampo add to generate a changeset file

🤖 Agent context

Autonomy: Human-driven (agent-assisted)

Pi was used to compare the Python release workflow with the Rust and Ruby release workflows, then update Python's publish job to follow Ruby's multi-job release pattern more closely. The key decisions were to keep the default workflow token in the publish job, remove explicit token wiring from tag creation, use git-based annotated tags plus release notes files like Ruby, make the root changelog an index to the package-specific changelogs, document the multi-package release setup, include a small changeset to test the release workflow after merge, and preserve fallback release notes when the latest changelog section is empty.

[greptile-apps]

_{Reviews (1): Last reviewed commit: "chore: align Python release publishing w..." | Re-trigger Greptile}

[github-actions]

posthog-python Compliance Report

Date: 2026-07-01 07:30:51 UTC
Duration: 176145ms

✅ All Tests Passed!

45/45 tests passed

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Capture Tests

✅ 29/29 tests passed

View Details

Test	Status	Duration
Format Validation.Event Has Required Fields	✅	516ms
Format Validation.Event Has Uuid	✅	1507ms
Format Validation.Event Has Lib Properties	✅	1507ms
Format Validation.Distinct Id Is String	✅	1507ms
Format Validation.Token Is Present	✅	1506ms
Format Validation.Custom Properties Preserved	✅	1507ms
Format Validation.Event Has Timestamp	✅	1506ms
Retry Behavior.Retries On 503	✅	9519ms
Retry Behavior.Does Not Retry On 400	✅	3506ms
Retry Behavior.Does Not Retry On 401	✅	3506ms
Retry Behavior.Respects Retry After Header	✅	9514ms
Retry Behavior.Implements Backoff	✅	23516ms
Retry Behavior.Retries On 500	✅	7512ms
Retry Behavior.Retries On 502	✅	7516ms
Retry Behavior.Retries On 504	✅	7511ms
Retry Behavior.Max Retries Respected	✅	23526ms
Deduplication.Generates Unique Uuids	✅	1500ms
Deduplication.Preserves Uuid On Retry	✅	7514ms
Deduplication.Preserves Uuid And Timestamp On Retry	✅	14521ms
Deduplication.Preserves Uuid And Timestamp On Batch Retry	✅	7505ms
Deduplication.No Duplicate Events In Batch	✅	1506ms
Deduplication.Different Events Have Different Uuids	✅	1506ms
Compression.Sends Gzip When Enabled	✅	1507ms
Batch Format.Uses Proper Batch Structure	✅	1507ms
Batch Format.Flush With No Events Sends Nothing	✅	1005ms
Batch Format.Multiple Events Batched Together	✅	1505ms
Error Handling.Does Not Retry On 403	✅	3509ms
Error Handling.Does Not Retry On 413	✅	3507ms
Error Handling.Retries On 408	✅	7510ms

Feature_Flags Tests

✅ 16/16 tests passed

View Details

Test	Status	Duration
Request Payload.Request With Person Properties Device Id	✅	1007ms
Request Payload.Flags Request Uses V2 Query Param	✅	1006ms
Request Payload.Flags Request Hits Flags Path Not Decide	✅	1006ms
Request Payload.Flags Request Omits Authorization Header	✅	1007ms
Request Payload.Token In Flags Body Matches Init	✅	1006ms
Request Payload.Groups Round Trip	✅	1009ms
Request Payload.Groups Default To Empty Object	✅	1006ms
Request Payload.Person Properties Distinct Id Auto Populated When Caller Omits It	✅	1006ms
Request Payload.Disable Geoip False Propagates As Geoip Disable False	✅	1007ms
Request Payload.Disable Geoip Omitted Defaults To False	✅	1006ms
Request Payload.Flag Keys To Evaluate Contains Only Requested Key	✅	1006ms
Request Lifecycle.No Flags Request On Init Alone	✅	502ms
Request Lifecycle.No Flags Request On Normal Capture	✅	1507ms
Request Lifecycle.Two Flag Calls Produce Two Remote Requests	✅	1010ms
Request Lifecycle.Mock Response Value Is Returned To Caller	✅	1003ms
Side Effect Events.Get Feature Flag Captures Feature Flag Called Event	✅	1509ms