CB-WP-0012-T03: ADR-0007 — render to HTML, and do not declare the port yet

Five decisions:

1. cb-render-html emits HTML/SVG/JS; the browser draws it. Rejected on
   measured marginal cost: egui+eframe 2,782,849; wgpu+winit 1,741,979;
   ratatui 1,067,013; macroquad 480,501; sdl2 191,973; fltk 140,079.
   The reason is allocation, not affordability — fltk is only 1.5x the
   corrected headroom, but wgpu is 12x fltk, unavoidable, and named by
   INTENT for stage 2. Stage 1 should not buy windowing stage 2 discards.

2. No cb-render-api and no cb-render-null. A port designed against one
   document-emitting implementation acquires a document's shape and
   stage 2 rewrites it. INTENT's second-use rule beats the blueprint's
   port pattern on timing. cb-render-html ships against Project.

3. AM-4 counts third-party code the project causes to be ACQUIRED, not
   runtimes the user already has. Browsers are not counted; sdl2 and
   fltk are counted at MORE than their Rust bindings. The rule costs
   more than it saves, which is the only reason to trust it here.

4. AM-4a's proc-macro defect (89,048 lines, 36.2%) is filed separately,
   not bundled with the request it unblocks.

5. Six controls bind the implementation, including a mutation-backed
   test that a token-less loopback request is refused, a bar on JS
   constructing commands, and a coverage gate asserting over the parsed
   emitted document rather than the Rust that emits it.

Reserved for the maintainer: AM-4a exceeds INTENT stage 2 by 7x and
cannot survive it; and whether decision 3's rule is the right one.

The hard gate held — no render implementation code before this commit.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

workplans/CB-WP-0012-render-port.md

@@ -161,7 +161,7 @@ outcome. Recorded as the CHAOS window's second entry.
 
 ```task
 id: CB-WP-0012-T03
-status: todo
+status: done
 priority: high
 ```
 
@@ -169,6 +169,17 @@ Record the decision, the rejected alternatives with their measured costs,
 and the controls the implementation must carry. No implementation code
 lands before this commits.
 
+**Done 2026-08-02.**
+[ADR-0007](../decisions/ADR-0007-render-html-not-a-port.md) — *render to
+HTML, and do not declare the port yet.* Five decisions, eight rejected
+alternatives with measured costs, six binding controls, and **two items
+reserved for the maintainer**: AM-4a's 7× incompatibility with stage 2, and
+whether the acquisition rule proposed by the pass that benefits from it is
+the right rule.
+
+The hard gate held: no render implementation code existed before this
+commit.
+
 ## Task: the port and its first implementation
 
 ```task