Draw FigJam connectors between related cards on the board

[jnwrnr]

User story

As a PM planning on a FigJam board, when I have two GitJam cards on the same board and the underlying GitLab issues are linked (blocks / blocked_by / relates_to), the widget should automatically draw a FigJam connector between the cards with an arrowhead matching the relationship direction.

Inspiration: Miro's Jira integration does this. When you drop two linked Jira cards on a Miro board, an arrow appears between them showing the dependency.

Scope

Discovery

• Scan the current page for other GitJam widget nodes via figma.currentPage.findAll(n => n.type === "WIDGET" && n.widgetId === OUR_WIDGET_ID).
• For each, read its useSyncedState("card", ...) to map widget node → issue reference (project path + iid).

Link resolution

• For the active card, fetch GET /projects/:id/issues/:iid/links.
• For each link, check whether the target issue is represented by another widget on the current page. Skip if not.

Connector creation

• For each matched pair, create a FigJam connector via figma.createConnector().
• connectorStart = source widget node via magnet "AUTO", connectorEnd = target widget node via magnet "AUTO".
• Arrow direction follows the link semantics:
  • blocks → arrow from blocker to blocked
  • is_blocked_by → same arrow inverted
  • relates_to → double-ended or neutral
• Connector colour / line style hints the type (e.g. red-ish for blocks, neutral grey for relates).

Stale connector cleanup

• Tag connectors created by GitJam (e.g. plugin-data on the connector: { gitjam: true, fromIid, toIid }).
• Before creating, check for an existing connector with the same endpoints + plugin data; skip duplicates.
• When a card is removed or its reference changes, remove the connectors we created for it.

Trigger

• Manual action on the card: "Connect related" button in the property menu.
• Possibly also on card load, but manual-first keeps surprises low.

Open questions / feasibility risks

• figma.createConnector() is documented for FigJam plugins. Need to verify it's callable from a widget event handler.
• Connector magnet positioning: "AUTO" should pick sensible edges. Verify with two cards side by side vs stacked.
• Cross-board limitation: only cards on the same page can be connected. Users who want cross-page relations see nothing.
• Large relationship graphs could create a lot of connectors – add a cap (e.g. max 10 per card) to avoid visual noise.

Prior art

• Miro Jira integration's "visualise dependencies" feature.
• The widget-typings widgetApi.1.0.0 surface does include node-creation APIs in FigJam – to be verified in a quick spike before full implementation.

Dependencies

Builds on #19 (linked issues data is the same endpoint). Ship #19 first as the data/UX fallback, then this as the visual stretch.

Acceptance criteria

• Action on the card triggers a scan + connector creation.
• Connectors only appear between pairs that are both on the current page.
• Arrow direction matches the GitLab link type.
• Duplicate prevention via plugin-data tags.
• When the action runs a second time, no new duplicate connectors appear.
• Removing a card cleans up its GitJam-owned connectors.