content: Phase 5 — rich inline text via structured runs (861/861)

CtText.text may be a list of runs (text marks href); CtHeading/CtQuote rich,
CtCode verbatim. New runs.sx overrides render/markdown/text methods (byte-
identical for plain strings, opt-in). 4 modes: HTML tags / markdown / nested
SX / plain asText (drift-proof). find-replace per-run marks-preserving;
search across run boundaries; CRDT block-granularity LWW; data+wire round-trip.
Runs are a Smalltalk-renderable list (not a dict — substrate can't read dict
fields under nested render dispatch). +36 tests (44 suites). Phase 6 (char-
level inline CRDT) recorded as future.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/content/conformance.sh

@@ -15,7 +15,7 @@ if [ ! -x "$SX_SERVER" ]; then
   fi
 fi
 
-SUITES=(block doc render api meta page page-full markdown text section compose tree-edit move block-path clone query toc anchor outline flatten transform normalize find-replace stats summary index table callout media data wire validate sanitize store snapshot crdt crdt-tree crdt-blocks crdt-store sync md-import md-doc fed)
+SUITES=(block doc render api meta page page-full markdown runs text section compose tree-edit move block-path clone query toc anchor outline flatten transform normalize find-replace stats summary index table callout media data wire validate sanitize store snapshot crdt crdt-tree crdt-blocks crdt-store sync md-import md-doc fed)
 
 OUT_JSON="lib/content/scoreboard.json"
 OUT_MD="lib/content/scoreboard.md"
@@ -69,6 +69,7 @@ run_suite() {
 (load "lib/content/page.sx")
 (load "lib/content/page-full.sx")
 (load "lib/content/markdown.sx")
+(load "lib/content/runs.sx")
 (load "lib/content/validate.sx")
 (load "lib/content/sanitize.sx")
 (load "lib/content/store.sx")