Add a slide with a heading, some text and a background colour or picture

The first choice for a slide that is only words: adds a designed text slide from plain parameters, rendered as an image at the slideshow's size with no AI: {"heading": "Lunch moved to 1pm", "text": "Same menu, new time.", "backgroundColor": "#0F172A"}. Only heading is required; text and cta are optional. How much each carries depends on the layout and the screen (a heading up to 60 characters, text up to 200 with heading-text, a cta up to 55 with heading-text-cta, and a heading of 50 to 80 characters beside a picture, depending on the screen; the full table is in agents.md), and text in capitals fits about 30% fewer. The background is one of backgroundColor (hex), mediaAssetId (an image from POST /v1/media) or mediaUrl (an image URL, downloaded and stored); with none it is the workspace accent colour (a dark navy when it has none), with text colour chosen to stay readable. A separate picture beside the text is imageMediaAssetId or imageUrl. branding: true adds the workspace logo and accent colour (nothing is added for a workspace without a logo). Once the workspace has a confirmed brand guide (GET /v1/brand), branding is on by default and the slide takes the guide's colours, font, logo and header band; send branding: false to opt out. A backgroundColor you name still wins. layout is heading, heading-text, heading-text-cta, heading-image-right or heading-image-left (the picture layouts need a picture, and take text and cta as optional), chosen from the fields when omitted. position (zero-based, appended when omitted) and durationSeconds (1 to 99, sized to the text when omitted) are optional. Returns the slide id, the designId the web app can edit, a previewUrl image link and the layout used. Text longer than the layout fits, a duration outside 1 to 99, a layout that does not fit the fields, or two backgrounds answer ValidationFailed naming the field (and, for text, the number that fits); nothing is clipped. The text is shown exactly as sent and is not checked for accuracy, and the slide is already in the slideshow when the answer arrives (undo removes it). When the layouts do not offer enough flexibility, add a finished image with POST /v1/slideshows/{id}/slides instead. Open on every plan.