chore(main): release 8.0.0

[flixopt-release-bot]

🤖 I have created a release beep boop

8.0.0 (2026-07-27)

⚠ BREAKING CHANGES

• the serialized clustering format changed - slice dims are now stored as 'period' (was '_period') plus a new 'dim_names' key. Clustering artifacts saved to JSON/netCDF by an older flixopt no longer load for apply_clustering()/expand() in this version; re-run transform.cluster() to regenerate them. Fresh clustering and same-version round-trips are unaffected. Also raises the minimum tsam_xarray to 0.6.4.

Bug Fixes

• dimension-aware effect-total consistency check (#745) (2b2720c)
• load clustered NetCDF files written before flixopt 7.0 (#757) (f8e53bd)
• load pre-7.0 clustered NetCDF files with legacy original_data refs (#742) (6962e5e)
• support linopy 0.9.0 (#758) (051480b)

Code Refactoring

• drop clustering dim-rename layer via tsam-xarray DimNames (#739) (cc56774)

---

This PR was generated with Release Please. See documentation.

[FBumann]

Maintainer note — this PR was hand-edited, not regenerated.

Release-please produced this as 8.0.0; the branch has been edited down to 7.3.0 (manifest, CITATION.cff, CHANGELOG heading, PR title) and the ⚠ BREAKING CHANGES notice removed.

The major came entirely from the BREAKING CHANGE: footer on #739, which was reverted in #746. Release-please does not pair a revert with its original, so the footer kept counting even though the code is gone.

Evidence there is no breaking change

Artifacts produced by released versions, loaded against current main:

written by	loads	expands
7.2.3 (plain)	yes	yes
7.2.3 (multi-period)	yes	yes
6.2.1 (plain, solved, multi-period, period+scenario)	yes (via #757)	yes
6.1.0 (plain)	yes (via #757)	yes

Cluster assignments compare equal per slice, and an expanded solved file reproduces each original cluster from its typical cluster. Serialized clustering is compatible with 7.2.1, and 6.x files that broke under 7.0 load again — strictly more compatible than the predecessor, not less.

Minor rather than patch because the release adds compatibility that did not previously exist: linopy 0.9.0 support (#758) and pre-7.0 clustered file loading (#757).

Before merging

• Merge this before landing anything else on main. Any new commit regenerates this PR and recomputes 8.0.0 from refactor: drop clustering dim-rename layer via tsam-xarray DimNames #739's footer, discarding the edits.
• fix: support tsam_xarray 0.6.5 by using cluster_counts #755 is not included. It is still open and raises the tsam_xarray floor to 0.6.5. Without it, 7.3.0 keeps the floor at 0.6.1 and users resolving to 0.6.5 hit a cluster_weights deprecation failure. To ship it in 7.3.0, merge it first — this PR will then need retargeting again.
• refactor: drop clustering dim-rename layer via tsam-xarray DimNames #739's footer will keep forcing a major on every future release PR until v8 genuinely ships. A commit whose branch commit message (not PR body) carries Release-As: survives this repo's squash strategy; a footer in the PR body does not.

[flixopt-release-bot]

🤖 Created releases:

• v8.0.0

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