[Zburgers]

Planning only

This PR contains no runtime implementation. It defines the proposed v1.3 rendering-engine architecture and the Shipyard execution plan.

Proposed v1.3 boundary

• modular per-render pipeline around the existing Marked + DOMPurify + KaTeX + Mermaid stack
• deterministic heading IDs + structured outline metadata
• clean, collapsible responsive Outline panel
• ordinary relative Markdown links, including cross-document heading navigation
• stronger local image/resource resolution and visible failure states
• image lightbox
• safe syntax highlighting + copy controls
• expanded Obsidian-compatible callouts, ==highlights==, footnotes, bounded per-render math
• generic fenced Mermaid rendering, including supported chart grammars, plus expanded viewing
• table/reader polish and kitchen-sink/security/performance qualification

Explicitly not v1.3

No graph view, backlinks, vault/workspace indexing, global search, transclusion, plugin system, or Agent Context Inspector.

Architecture decision

ADR-0002 proposes keeping the hardened v1.2.5 parser/security stack and introducing a structured src/rendering/ subsystem instead of migrating to unified/remark or MDX/React rendering.

Review gates before implementation

Please approve the product boundary, ADR-0002, parent-relative local-image policy, dependency choices, and 19-task Shipyard plan.

After this planning PR is approved/merged, implementation should start on a fresh feature branch from the merged planning commit. This PR does not authorize a v1.3 release or version/tag change.