Release v6.7.0

Screens can now carry the sketches, mockups and images they were designed from, slices can show linked copies of events and read models declared elsewhere, and model elements can link to issues in GitHub, Jira, Linear or another tracker.

Added

• A screen can carry sketch <path>, mockup <path> (one line per HTML page) and image <path> lines that name files beside the model, relative to the model root. They are kept in source, printed, carried through the AST and MCP tools, and never change what the screen does. The compiler reports PLAY0950 for a line without a path and PLAY0951 for an image that is not PNG, JPG, GIF, SVG or WebP or a mockup that is not an HTML page; opening a model root (CLI, MCP) warns with PLAY0952 about a file that is missing or outside the root. See Sketches, mockups and images. (#1191)
• shows event <Name> and shows readmodel <Name> in a slice place a linked copy of an element declared in another slice. The event model board draws a placed event again with sourceEventId pointing at its declaration and lists placed read models on the slice; renaming the declaration renames every placement. PLAY0953 refuses a malformed line, PLAY0954 warns about an unknown element and PLAY0955 about an element the slice already declares or shows twice. See Show an element in more than one slice. (#1193)
• Model notes have a new issue kind that links the anchored element to issues in an external tracker. Each reference names its tracker (github, jira, linear or other), the issue key as id and an optional url; list-model-notes filters by kind: "issue" and by issue key. See Link elements to issues. (#1192)
• Monaco and the VS Code extension complete, explain and highlight sketch, mockup, image and shows.