CLAUDE.md: adopt the condensed structure, updated to current truth (-503/+176)

Reconciles the wip/main-local-claudemd-condensation distillation (made
~2026-06-03 by a parallel session) onto post-merge main:

- Current state section: ONE status block (<=5 lines + pointers, by
  rule) + canonical reading order + the two digest entry points + the
  divergence register; replaces status sediment scattered through
  Goal/Roadmap sections.
- Kept from the merged main (the condensation predated them): the
  memory/digest rule in How to operate, the divergence-register
  section + phase-checklist item, de-dated milestone rules.
- Dropped: shipped-phase ship-notes, stale next-phase candidate lists,
  the superseded reference_render_pipeline_state pointer.
- Also salvaged from the wip branch: .gitignore entries (.obsidian/,
  claude-memory junction) + pdb_extract.py __main__ guard. The wip's
  TextureDump edit predates main's args support (discarded) and its
  physics-probe edits were STRIP-marked leftovers (discarded).

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

.gitignore

@@ -81,3 +81,9 @@ substep_trace*
 sg_built.txt
 # Stray bash-mangled path artifacts from PowerShell-via-bash escaping
 C[€-￿]*
+
+# Obsidian vault config (personal, not project-wide)
+.obsidian/
+
+# Junction to Claude Code per-project memory (Obsidian vault visibility)
+claude-memory