[Flix6x]

Description

Closes #231: the changelog stopped at v0.1.1. It now covers all 48 releases up to v0.9.6, plus an Unreleased section for what is on main since then (#225).

• Format: Keep a Changelog, in reStructuredText so that the docs keep including it as they are.
  Each version has its release date and a link to its changes since the previous version.
  Entries are grouped under Added, Changed, Deprecated, Removed, Fixed and Security, and end in links to their PRs.
  Breaking changes are marked as such (v0.2.1 moved the exception classes, v0.3.3 made S2 an optional extra).
• S2 in its own changelog: changes to the S2 integration are listed in CHANGELOG-S2.rst.
  CHANGELOG.rst still has every release, and each release that changed the S2 integration links to its section in the S2 changelog.
  S2 sections link back to releases that also made other changes.
  The links use the anchors GitHub gives the release headings (e.g. #v090--2026-04-21), as the docs are read on GitHub.
  They point at main, so they resolve once this is merged.
  The breaking change that made S2 an optional extra (v0.3.3) is listed in both.
• Sources: the PRs in each tag range, found from squash-merge, merge and backport commit subjects.
  PRs merged into feature branches (e.g. Add belief_time_measured_instantly parameter to data upload API #140, Add backward-compatible JSON field parsing to asset and sensor methods #165, feat: warn when using aggregate-power flex-context field with server < 0.31.0 #182) are listed under the PR that brought them to main.
  Releases without PRs are described from their commits.
• Dates: those of the PyPI uploads. Five tags never reached PyPI (v0.1.2, v0.1.3, v0.2.2, v0.2.3, v0.5.2), so they use the tag date and say so.
• Release history quirks: v0.9.1 to v0.9.3 were backports from a maintenance branch, so v0.9.4 lists only what was new since v0.9.0 and says it also contains those fixes. v0.9.5 is the same commit as v0.9.4.
• Keeping it current: a PR template with a changelog checkbox, a step in CONTRIBUTING.rst for adding an entry to the right changelog, and release steps for rolling Unreleased over to the new version in both.

Left out of #231's proposal, for later:

• A CI check that fails when src/ changes without a changelog entry.
• Taking the GitHub release notes from the changelog instead of generating them from commit messages.

Once this is merged, #230 needs an entry under Unreleased.

How to test

• Read CHANGELOG.rst, or the rendered changelog page after building the docs (sphinx-build -b html docs docs/_build/html).
• docutils reports no warnings for CHANGELOG.rst and CHANGELOG-S2.rst.
• All 35 links between the two changelogs match the heading anchors on GitHub's rendering of this branch's CHANGELOG.rst.

🤖 Generated with Claude Code

https://claude.ai/code/session_01KVweu7HHCzk5yhWTskgjva

[coveralls]

Coverage Report for CI Build 39041949348

Coverage remained the same at 95.991%

Details

• Coverage remained the same as the base build.
• Patch coverage: No coverable lines changed in this PR.
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	923
Covered Lines:	886
Line Coverage:	95.99%
Coverage Strength:	9.6 hits per line

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💛 - Coveralls