A picture off the pasteboard becomes a card's file, its hero, or the board's backdrop

⌘V grows an image-data branch, below the app's own clipboard format and refused
outright while a file URL is on the pasteboard: a screenshot or a browser's Copy
Image lands as "Pasted Image.png" in the anchor card's attachments/, through the
very import path Finder file drops and ⇧⌘A take — one bracket, one Finder-style
collision ladder, one set of banners, and the same silence a drop's arrival has.
A card window's ⌘V pastes onto its own card; a focused text field still wins the
selector natively. A file-shaped flavor travels byte for byte, PNG preferred when
several are offered; TIFF and BMP are re-encoded to PNG, being interchange
encodings rather than files anyone wants in a folder.

The hero key gets the setter it was born owing: "Set as Hero" on any image row of
the attachment list, "Remove Hero" on the row that holds it, with menu-bar twins
so the context entry is nobody's only home. It writes as a restyle — one key, one
bracket, one invertible step on the window's own stack — and replaces rather than
refusing, because a card has one hero and the row that has it says Remove instead.

Edit ▸ Paste as Board Background is the same payload's other destination, taking
the existing background.image convention at its word: the picture into the board
folder as "Pasted Background.png", the colour subkey untouched, the generator's
overwrite-our-own-name rule inherited and its echo memo taught to tell the two
producers apart.

Claude-Session: https://claude.ai/code/session_014PtZdPwqZuqEDLc6wZMtEy

DESIGN/05-card-window.md

@@ -58,7 +58,8 @@ Stacked sections under small-caps headers, in this order; quiet rows, read-optim
 
 - Shows **every top-level file of `attachments/`** — including files also embedded in the body (settled: the section is the card's complete file inventory, no reference-tracking magic; an image appearing in both places is honest, not a bug). Subfolders are tolerated but not surfaced (01-storage-format.md's attachments rules).
 - **Compact rows**: small QuickLook thumbnail (Finder-icon fallback) + middle-truncated filename, one row per file. The section header carries a quiet add affordance; empty, the section stays with a one-line hint (drop files, or File ▸ Add Attachment…, ⇧⌘A) — the drop surface remains the **whole window** (name collisions auto-rename, Finder-style — 01-storage-format.md). **Drop precedence is split by payload** (settled): file drops import as attachments anywhere in the window — Edit mode included, the text editor never intercepts a file drop; dragged *text* lands in the Edit editor at the caret within its bounds as ordinary insertion, and is inert elsewhere in the window. **One carve-out by hover target** (ruled 2026-07-29 — comment attachments are authorable): a file dropped **within the comment composer's bounds** imports to the draft's `attachments/`, and within an **inline comment edit session's bounds** to that comment's — the window-wide card default covers everywhere else (The comments column below).
-- Row interactions: double-click or Return opens; context menu Open / Reveal in Finder / Remove (moves to the **system** Trash, never hard-deletes — 03-board-ui.md's naming constraint keeps this distinct from board deletion); rows drag out their file URL.
+- Row interactions: double-click or Return opens; context menu Open / Reveal in Finder / **Set as Hero** or **Remove Hero** / Remove (moves to the **system** Trash, never hard-deletes — 03-board-ui.md's naming constraint keeps this distinct from board deletion); rows drag out their file URL. **The hero row is one slot with two words** (ruled 2026-08-09, 03-board-ui.md § Card face ▸ Hero image): "Set as Hero" on any image row that is not already the hero, "Remove Hero" on the one that is, and **nothing at all** on a row that can be neither — present-or-absent rather than greyed, because a disabled "Set as Hero" on a `.zip` would claim a capability that will never arrive (Remove, just below it, greys under the lock as before). Removing the hero removes the *key*, never the file. The row that is the hero says so to VoiceOver as its value.
+- **⌘V pastes a picture onto this card** (04-interactions.md ▸ Clipboard's image-data branch): the whole-window drop's keyboard twin, landing in the same `attachments/` through the same import path. A focused text field — the body editor, the composer, an inline comment edit — consumes ⌘V natively and stays a text paste, which is the drop precedence's rule arriving on the other input.
 - **Keyboard-native, new in the rewrite** (the pathfinder's strip was pointer-only): the section is focusable; arrows move between rows, **Space QuickLooks** the selected row, Return opens it, ⌫ removes it (same system-Trash semantics).
 
 ### Style