feat(slides): import slidey-flavored markdown decks

[njreid]

Summary

Extends gog slides create-from-markdown to import slidey-flavored markdown decks (the univrs/slidey/slides/index.md-style format) into Google Slides.

• Per-slide YAML frontmatter — layout: title|hero|center|default|two-cols|three-cols|statement, content: wide|narrow (parsed; not yet applied to text-box widths).
• ## Notes speaker notes — the trailing ## Notes (or ### Notes) section is hoisted into the slide's speaker notes; FA shortcodes inside notes are stripped to plain text.
• Font Awesome shortcodes — :fa-name: / :fas-name: / :far-name: / :fab-name: (and free-tier :fal-/:fad- substitutions) resolve to FA Free SVGs from jsDelivr, uploaded to Drive and inserted as images.
• Mermaid diagrams — fenced ```mermaid blocks render to PNG via local mmdc (configurable, optional) and insert as full-width images.
• Multi-column layouts — ::cols:: / ::col2:: / ::col3:: / ::right:: (synonym for ::col2::) / ::/cols::.
• ::boxes:: / ::arrows:: blocks — flatten to bulleted body lines with optional inline icons.
• Hero / title / statement layouts — h1 stays in body, rendered at 44pt centered.
• New CLI flags on gog slides create-from-markdown:
  • --fa-style (default solid) — default FA style for prefix-less shortcodes
  • --mmdc (default mmdc) — path to mermaid CLI
  • --strict — treat any skipped FA/diagram asset as fatal
  • --keep-temp-images — don't delete temporary Drive uploads
  • --no-notes — discard ## Notes sections
• Existing --dry-run prints the would-be BatchUpdatePresentationRequest JSON with gogcli://pending/... placeholder URLs (no network).

Built as a clean three-stage pipeline: pure parser → asset pipeline (Drive uploads behind an Uploader interface) → renderer (typed Slide AST → []*slides.Request). Asset failures warn-and-skip unless --strict. Drive uploads are tracked and best-effort cleaned up on completion.

Design + Plan

• Spec: docs/superpowers/specs/2026-05-13-slidey-import-design.md
• Plan: docs/superpowers/plans/2026-05-13-slidey-import.md

Test plan

• go build ./... && go vet ./... clean
• go test ./internal/cmd/... passes (only pre-existing TestRequireAccount_Missing fails — env-dependent, unrelated)
• End-to-end fixture test in internal/cmd/slides_e2e_test.go parses the real 969-line univrs/slidey/slides/index.md and asserts presence of every layout kind, notes, FA icons, and mermaid blocks; renderer produces non-empty output with a fake asset map
• Manual dry-run smoke: gog slides create-from-markdown "Smoke" --content-file testdata/slidey/index.md --dry-run produces a clean BatchUpdatePresentationRequest JSON with gogcli://pending/fa-... and gogcli://pending/diagram-... placeholders
• Live smoke test against a real Google account (recommend running before merge): gog slides create-from-markdown "Slidey Import Test" --content-file testdata/slidey/index.md --account <you> and confirm icons + mermaid render in the resulting deck

Notes for reviewers

• New parser/renderer code is in internal/cmd/slides_markdown_*.go, internal/cmd/slides_layout.go, internal/cmd/slides_assets.go, internal/cmd/slides_formatter.go.
• The legacy Slide / SlideElement types and the old SlidesToAPIRequests / CreatePresentationFromMarkdown were replaced (the new replacement reuses SlidesToAPIRequests as a thin wrapper for back-compat).
• docs/commands/gog-slides-create-from-markdown.md was hand-edited; if you have a docs generator (make docs-commands?) it should be re-run before release to pick up the 5 new flags.
• The image-emission loop in RenderSlides walks top-level slide.Body only — diagrams/icons inside ColumnsBlock are silently skipped (v1 limitation, documented in code).
• ASCII byte-length is used to compute the 44pt title text range on hero/title/statement layouts; emoji/multi-byte titles will get wrong indices (acceptable for v1).

🤖 Generated with Claude Code