MAINT-21: tests read and patch the Controller through tools/main_files.py

Prepares the split of app/main.py's Controller into files by job, with no app
change. tools/main_files.py gives a test the text and the AST of main.py plus
the files split from it, and `live`, which sets a global in every file whose
functions read it (and raises when none does). Tests that read main.py's
source, and tests and replay tools that patch a main global (datetime,
compute, resolve, _mono, WRITE_BUDGET_S, ...), go through it, so they pass on
this layout and on the split one. test_split_patches.py fails when a test or
tool patches an app.main attribute that main.py no longer reads, or that
another file also reads. tools/maint21_same_ast.py proves every function,
method and module-level assignment of main.py at the base is found unchanged
in its new file.

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

goodwe_controller/test_maint13.py

@@ -520,9 +520,11 @@ check("a fixed tariff set up counts as a gate: outside its cheap hours a pack "
       "that is not charging is closed, inside them it is open",
       c._price_gated is True
       and c._charge_gate_open(c.inverters[0]) is c.cheap)
+sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)), "tools"))  # noqa: E402
+import main_files  # noqa: E402
 import app.main as main_mod                                     # noqa: E402
-_real_gated, _calls = main_mod.static_gated, []
-main_mod.static_gated = lambda o, now: _calls.append(now) or _real_gated(o, now)
+_real_gated, _calls = main_files.live.static_gated, []
+main_files.live.static_gated = lambda o, now: _calls.append(now) or _real_gated(o, now)
 try:
     c._gated_key = None
     read(c)
@@ -530,7 +532,7 @@ try:
     read(c)
     c._static_gated(c.o, datetime.now(UTC) + timedelta(hours=1))
 finally:
-    main_mod.static_gated = _real_gated
+    main_files.live.static_gated = _real_gated
 check("...worked out once an hour, not on every tick (3 reads in one hour = 1 "
       f"build; a new hour = 1 more): {len(_calls)} builds",
       len(_calls) == 2 and c._price_gated is True)