chore(examples): remove 9 legacy demos superseded by canonical set

The 5-tier canonical set (01_static → 05_realtime) replaces the prior
hand-written demos completely. The new set is structured, tested, and
each tier exercises a distinct slice of the framework. Git history is
the archive — no transitional _legacy/ directory.

Removed: basic_pwa, broadcast, full_pwa, hello_world, quickstart,
reactivity, rpc_call, server_realtime, simple_client. Updates the
AGENTS.md layout description to point at the new set.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: apiad

AGENTS.md

@@ -38,7 +38,7 @@ violetear/          package source
   presets.py        FlexGrid, SemanticDesign, UtilitySystem, Atomic
 tests/              pytest suite
 docs/               quarto docs site + example .py files (consumed by test_examples.py)
-examples/           hand-written demos (hello_world, reactivity, full_pwa, …)
+examples/           canonical demos, one per tier (01_static → 05_realtime)
 issues/             design docs for unimplemented features
 .github/workflows/  CI (ruff format-check + pytest on push/PR)
 roadmap.md          v1.0 roadmap (Phases 1-4)