terminology: spawn → pour/wisp for molecules (gt-9uy0)

Molecules use chemistry verbs, not spawn:
- pour = create persistent mol (liquid)
- wisp = create ephemeral wisp (vapor)
- spawn = polecats only (workers)

Changes:
- Delete chemistry-design-changes.md (migration doc)
- Remove migration tables from sling-design.md
- Update bond tables: Spawn → Pour/Wisp
- Rename spawnMoleculeFromProto → pourMoleculeFromProto
- Rename spawnMoleculeOnIssue → runMoleculeOnIssue
- Update templates: bd mol spawn → bd wisp
- Update prime.go: commands and messages
- Clean all docs and comments

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docs/architecture.md

@@ -604,7 +604,7 @@ Some workflows need **dynamic structure** - steps that emerge at runtime based
 on discovered work. Consider mol-witness-patrol: it monitors N polecats where
 N varies. A static molecule can't express "for each polecat, do these steps."
 
-The solution is **dynamic bonding** - spawning child molecules at runtime:
+The solution is **dynamic bonding** - creating child molecules at runtime:
 
 ```bash
 # In survey-workers step: