mtg_python_deckbuilder/RELEASE_NOTES_TEMPLATE.md

# MTG Python Deckbuilder ${VERSION}

## Unreleased (Draft)

### Added
- Theme picker performance: precomputed summary projections + lowercase haystacks and memoized filtered slug cache (keyed by (etag, q, archetype, bucket, colors)) for sub‑50ms typical list queries on warm path.
- Skeleton loading UI for theme picker list, preview modal, and initial shell.
- Theme preview endpoint (`/themes/api/theme/{id}/preview` + HTML fragment) returning representative sample with roles (payoff/enabler/support/wildcard/example/curated_synergy/synthetic).
- Commander bias heuristics in preview sampling (color identity filtering + overlap/theme bonuses) for context-aware suggestions.
- In‑memory TTL (600s) preview cache with metrics (requests, cache hits, average build ms) exposed at diagnostics endpoint.
- Web UI: Double-faced card (DFC) hover support with single-image overlay flip control (top-left button, keyboard (Enter/Space/F), aria-live), persisted face (localStorage), and immediate refresh post-flip.
- Diagnostics flag `WEB_THEME_PICKER_DIAGNOSTICS=1` gating fallback description flag, editorial quality badges, uncapped synergy lists, raw YAML fetch, and metrics endpoint (`/themes/metrics`).
- Catalog & preview metrics endpoint combining filter + preview counters & cache stats.
- Performance headers on list & API responses: `X-ThemeCatalog-Filter-Duration-ms` and `ETag` for conditional requests.
 - Cache bust hooks tied to catalog refresh & tagging completion clear filter/preview caches (metrics now include last bust timestamps).
 - Governance metrics: `example_enforcement_active`, `example_enforce_threshold_pct` (threshold default 90%) signal when curated coverage enforcement is active.
 - Server authoritative mana & color identity fields (`mana_cost`, `color_identity_list`, `pip_colors`) included in preview/export; legacy client parsers removed.

### Changed
- Preview assembly now pins curated `example_cards` then `synergy_example_cards` before heuristic sampling with diversity quotas (~40% payoff, 40% enabler/support, 20% wildcard) and synthetic placeholders only when underfilled.
- List & API filtering route migrated to optimized path avoiding repeated concatenation / casefolding work each request.
- Hover system consolidated to one global panel; removed fragment-specific duplicate & legacy large-image hover. Thumbnails enlarged & unified (110px → 165px → 230px). Hover activation limited to thumbnails; stability improved (no dismissal over flip control); DFC markup simplified to single <img> with opacity transition.

### Deprecated
- (None new)

### Fixed
- Resolved duplicate template environment instantiation causing inconsistent navigation globals in picker fragments.
- Ensured preview cache key includes catalog ETag preventing stale samples after catalog reload.

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### Added
- Theme whitelist governance (`config/themes/theme_whitelist.yml`) with normalization, enforced synergies, and synergy cap (5).
- Expanded curated synergy matrix plus PMI-based inferred synergies (data-driven) blended with curated anchors.
- Test: `test_theme_whitelist_and_synergy_cap.py` validates enforced synergy presence and cap compliance.
- PyYAML dependency for governance parsing.

### Changed
- Theme normalization (ETB -> Enter the Battlefield, Self Mill -> Mill, Pillow Fort -> Pillowfort, Reanimator -> Reanimate) applied prior to synergy derivation.
- Synergy output capped to 5 entries per theme (curated > enforced > inferred ordering).

### Fixed
- Removed ultra-rare themes (frequency <=1) except those protected/always included via whitelist.
- Corrected commander eligibility: restricts non-creature legendary permanents. Now only Legendary Creatures (incl. Artifact/Enchantment Creatures), qualifying Legendary Artifact Vehicles/Spacecraft with printed P/T, or any card explicitly stating "can be your commander" are considered. Plain Legendary Enchantments (non-creature), Planeswalkers without the text, and other Legendary Artifacts are excluded.

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