[SeanShaffer88]

Second slice of the Dolphin-parity program (tags/ratings/comments, now in scope). Supersedes #154, whose branch could not be updated with the Recycle Bin merge through the file-push route (the merge structure was lost and GitHub reported conflicts); this branch carries the identical final tree, based on current main.

• Core FileMetadataStore: Meridian's own per-item metadata in one local JSON file keyed by full path — tags (normalized: trimmed, de-duplicated, capped), a 0–5 star rating, and a comment. Atomic quiet saves; a damaged file reads as empty; clearing an item's metadata removes its entry. Nothing is written into the user's files, so this works for every file and folder (the Properties window still edits embedded file properties separately).
• The pane right-click menu gains "Tags & rating…": an editor dialog for the selection. Tags and the rating apply to every selected item; the comment is single-item only. Saved values show as lines in the pane's preview block (tags, ★ rating, comment). In the Recycle Bin the item is disabled, and recycled items are keyed by their original path.

Still to come for full parity on this roadmap line: searching/filtering by tags and the NTFS ADS investigation. Local gate green on this exact tree; Windows CI is the App build check. Runtime Unverified.