Self-hosted z3.sx translator, prove.sx prover, parser unicode, auto reader macros

- z3.sx: SX-to-SMT-LIB translator written in SX (359 lines), replaces Python translation logic
- prove.sx: SMT-LIB satisfiability checker in SX — proves all 91 primitives sat by construction
- Parser: support unicode characters (em-dash, accented letters) in symbols
- Auto-resolve reader macros: #name finds name-translate in component env, no Python registration
- Platform primitives: type-of, symbol-name, keyword-name, sx-parse registered in primitives.py
- Cond heuristic: predicates ending in ? recognized as Clojure-style tests
- Library loading: z3.sx loaded at startup with reload callbacks for hot-reload ordering
- reader_z3.py: rewritten as thin shell delegating to z3.sx
- Split monolithic .sx files: essays (22), plans (13), reactive-islands (6) into separate files

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

shared/sx/jinja_bridge.py

@@ -98,7 +98,7 @@ def load_sx_dir(directory: str) -> None:
     Skips boundary.sx — those are parsed separately by the boundary validator.
     """
     for filepath in sorted(
-        glob.glob(os.path.join(directory, "*.sx"))
+        glob.glob(os.path.join(directory, "**", "*.sx"), recursive=True)
     ):
         if os.path.basename(filepath) == "boundary.sx":
             continue
@@ -112,6 +112,12 @@ def load_sx_dir(directory: str) -> None:
 
 _watched_dirs: list[str] = []
 _file_mtimes: dict[str, float] = {}
+_reload_callbacks: list[Any] = []
+
+
+def register_reload_callback(fn: Any) -> None:
+    """Register a function to call after hot-reload clears and reloads components."""
+    _reload_callbacks.append(fn)
 
 
 def watch_sx_dir(directory: str) -> None:
@@ -119,7 +125,7 @@ def watch_sx_dir(directory: str) -> None:
     _watched_dirs.append(directory)
     # Seed mtimes
     for fp in sorted(
-        glob.glob(os.path.join(directory, "*.sx"))
+        glob.glob(os.path.join(directory, "**", "*.sx"), recursive=True)
     ):
         _file_mtimes[fp] = os.path.getmtime(fp)
 
@@ -129,7 +135,7 @@ def reload_if_changed() -> None:
     changed = False
     for directory in _watched_dirs:
         for fp in sorted(
-            glob.glob(os.path.join(directory, "*.sx"))
+            glob.glob(os.path.join(directory, "**", "*.sx"), recursive=True)
         ):
             mtime = os.path.getmtime(fp)
             if fp not in _file_mtimes or _file_mtimes[fp] != mtime:
@@ -137,6 +143,9 @@ def reload_if_changed() -> None:
                 changed = True
     if changed:
         _COMPONENT_ENV.clear()
+        # Reload SX libraries first (e.g. z3.sx) so reader macros resolve
+        for cb in _reload_callbacks:
+            cb()
         for directory in _watched_dirs:
             load_sx_dir(directory)