refactor: Extract Ali je vroče read model

[jalezi]

Stacking note

This PR is stacked on #416 and should be reviewed against chore/prepare-repo-for-agents, not directly against main.

That matters because the new frontend-check workflow runs yarn typecheck, which depends on the TypeScript configuration fix from #416. The unrelated chore/upgrade-yarn-deps branch is no longer part of this branch chain.

Why

The Ali je vroče flow had several read-model responsibilities spread across the Solid hook, query helpers, network helpers, and an optimistic-update utility. Understanding station selection required following localStorage preference migration, station shape conversion, current-hotness display mapping, raw Datasette/Vremenar transformations, cache lookup behavior, and optimistic placeholders across multiple modules.

This PR deepens that module boundary by putting the station/current-hotness read model behind a plain TypeScript interface while preserving the existing UI-facing useWeatherData() return shape.

What changed

• Added code/ali-je-vroce/model/readModel.ts as a plain read-model module.
• Moved selected-station preference reading/writing, legacy migration, validation, and storage-error fallback into the read model.
• Moved station preference conversion and current-hotness display-field mapping into the read model.
• Moved raw Datasette station-row and Vremenar/percentile response transformations into the read model.
• Replaced the old optimistic-update utility with read-model-owned optimistic display policy and removed the orphaned file.
• Added Node test coverage for preference migration, storage failure fallback, malformed preferences, station conversion, display mapping, optimistic display, and raw response transformation.
• Added yarn test and wired yarn test plus yarn typecheck into the website build workflow.

Impact

The page behavior is intended to stay the same, with a few deliberate improvements:

• Station-switch optimistic cache lookup now uses the same string station id shape as the query cache.
• Malformed stored station preferences reset to the default station instead of leaking invalid shapes into UI state.
• Invalid/non-finite percentile values now fail fast instead of risking an incorrect current-hotness bucket.
• Preference storage errors still degrade gracefully, so blocked/unavailable localStorage does not break page initialization or station switching.

Follow-up

Created #417 for the next related slice: reducing duplicated query/cache fallback policy across hooks/queries.ts, utils/prefetching.ts, and hooks/useWeatherData.ts.

Validation

• yarn test
• yarn typecheck
• yarn build

[Copilot]

Pull request overview

This PR extracts the “Ali je vroče” station/current-hotness read model into a plain TypeScript module (with tests) while keeping the existing useWeatherData() UI-facing shape, and wires yarn test + yarn typecheck into CI.

Changes:

• Introduces code/ali-je-vroce/model/readModel.ts to own preference storage/migration, station shape conversion, current-hotness display mapping, optimistic display policy, and raw response transforms.
• Updates useWeatherData + helpers.ts to use the read model and removes the old optimistic-update utility.
• Adds Node test coverage for the read model and runs yarn test + yarn typecheck in the build workflow.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tsconfig.json	Adjusts TS path-mapping configuration comment / baseUrl usage.
skills-lock.json	Adds skills lock scaffold for agent-skill management.
README.md	Documents canonical vs generated agent skills locations and sync command.
package.json	Adds sync-skills, updates postinstall, adds test and typecheck scripts.
code/ali-je-vroce/utils/optimistic.ts	Removes legacy optimistic-update helper (now owned by read model).
code/ali-je-vroce/model/readModel.ts	New read-model module (prefs, transformations, optimistic display).
code/ali-je-vroce/model/readModel.test.ts	New Node tests for the read-model behavior.
code/ali-je-vroce/hooks/useWeatherData.ts	Switches UI hook to read-model state/transformations + new optimistic policy.
code/ali-je-vroce/helpers.ts	Delegates station/current-hotness transforms to the read model.
CLAUDE.md	Points Claude Code at the canonical agent instructions.
AGENTS.md	Adds canonical, tool-neutral agent instruction entrypoint and skills guidance.
.gitignore	Ignores generated .claude/skills copy.
.github/workflows/copilot-setup-steps.yml	Adds Copilot coding-agent setup workflow for consistent environment.
.github/workflows/build.yaml	Runs yarn test and yarn typecheck in CI before yarn build.
.github/instructions/typescript-solid-eleventy.instructions.md	Adds scoped frontend/TS/Solid/Eleventy guidance.
.github/instructions/testing.instructions.md	Adds scoped testing/validation guidance.
.github/instructions/security.instructions.md	Adds scoped security guidance for code/workflows/content/data.
.github/instructions/performance.instructions.md	Adds scoped performance guidance for site + frontend.
.github/instructions/documentation.instructions.md	Adds scoped docs/content guidance.
.github/instructions/code-review.instructions.md	Adds scoped code review guidance for this repo.
.github/copilot-instructions.md	Adds canonical repository-wide Copilot instructions.
.github/agents/software-engineer.agent.md	Adds “Software Engineer” agent definition.
.github/agents/reviewer.agent.md	Adds “Reviewer” agent definition.
.github/agents/debugger.agent.md	Adds “Debugger” agent definition.
.github/agents/architect.agent.md	Adds “Architect” agent definition.
.agents/skills/write-tests/SKILL.md	Adds reusable “write-tests” skill.
.agents/skills/setup-component/SKILL.md	Adds reusable “setup-component” skill.
.agents/skills/refactor-code/SKILL.md	Adds reusable “refactor-code” skill.
.agents/skills/generate-docs/SKILL.md	Adds reusable “generate-docs” skill.
.agents/skills/debug-issue/SKILL.md	Adds reusable “debug-issue” skill.
.agents/skills/code-review/SKILL.md	Adds reusable “code-review” skill.

[jalezi]

Accepted. The read model catches getItem/setItem/removeItem failures, but this comment catches the missing outer edge: evaluating localStorage itself can throw before the read-model fallback runs. Implemented getBrowserPreferenceStorage() in the Solid hook, which falls back to a no-op preference storage adapter when browser storage is unavailable. Covered by existing storage-failure read-model tests plus yarn test / yarn typecheck after the change. Commit: 49103f9.

[jalezi]

Accepted. Same underlying issue as the initialization path: passing localStorage directly means the getter can throw before writeSelectedStationPreference has a chance to handle storage errors. The hook now acquires preferenceStorage once through the safe wrapper and uses that same adapter for writes during station changes. Commit: 49103f9.