fix(loops): resolve custom media fields to URLs in loops

[shadysamir]

Summary

A loop over a data table only exposed the built-in featuredMedia and firstImage fields as resolved media URLs. Any user-defined media field (for example a Client logo) was spread through raw, so a {currentEntry.<field>} binding on an img src emitted the stored media id instead of a URL. The browser then resolved that bare id against the current path, so the image never loaded, both on the editor canvas and on the published site.

The format:"media" hint written into the binding at authoring time had no consumer at render time: id → URL dereferencing ran only for the two hardcoded built-in fields in the loop source.

This fix makes the loop source resolve every type:"media" cell to its public path generically, replacing the featuredMedia-only special case:

• Both page-slice queries (post-type published-version join and data-kind direct read) now select data_tables.fields_json to learn which fields are media-typed.
• collectMediaIds gathers the featured id plus every custom media id into the existing single batched resolve, so no extra queries are issued.
• resolvedMediaOverlay overwrites each media cell with its resolved public path in both row projections, spread right after the raw cells.
• Multi-value media fields (allowMultiple) flatten to the first element for a scalar binding; a dangling id resolves to null rather than leaking the raw id.

Resolving media in the loop source runs before both token paths, so resolveBindingValue and interpolateTokens need no changes: by the time they read the field, it is already a URL. A new shared reader readMediaCellIds (in src/core/data/cells.ts) tolerates both cell shapes (single id string, or string[]).

Scope is single-value resolution plus first-element flatten for multi-value. Rendering every element of a multi-value field is a separate nested-loop concern and is intentionally out of scope here.

Relates to #224 (same root limitation from the plugin-API side: resolveMediaIdsToPaths was hardcoded to built-in media fields).

Verification

• bun run build
• bun test (6302 pass, 0 fail; includes 5 new tests in dataRowsFetch.test.ts)
• bun run lint
• Docker/deployment check, if relevant

Checklist

• Tests cover behavior changes.
• Docs were updated when behavior, config, deployment, or public surfaces changed. (No documented behavior changed; the fix restores the documented format:"media" contract.)
• No compatibility shim was added for old pre-release behavior.
• No secrets, local databases, uploads, or generated artifacts are included.

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR fixes data.rows loop rendering so all media-typed table fields (not just the built-in featuredMedia / firstImage) are resolved from stored media asset IDs to public URLs before bindings are evaluated. This aligns loop output with the authoring-time format: "media" hint so {currentEntry.<field>} can be used directly in img src on both the editor canvas and published output.

Changes:

• Fetch data_tables.fields_json in both post-type and data-kind row queries to identify which fields are type: "media".
• Batch-resolve media IDs for featured media + all custom media fields, then overlay resolved URLs onto the row’s fields map.
• Add readMediaCellIds helper and new tests covering single, multi-value (flatten-first), empty, and dangling-ID behavior.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/core/loops/sources/dataRows.ts	Generalizes loop-source media resolution by discovering media fields from fields_json, batch-resolving IDs, and overlaying URLs into LoopItem.fields.
src/core/data/cells.ts	Adds readMediaCellIds to tolerate both single-id and multi-id media cell shapes (string vs string[]).
src/tests/loops/dataRowsFetch.test.ts	Adds coverage to lock in URL resolution for custom media fields across both loop projections (data-kind + post-type).

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.