Quote CPPDEFINES, warn on env access, degrade unmodelled subscripts, realify InvalidLibrary

CPPDEFINES joins the quoted buckets (a spaced define no longer splits
across tokens) and its tuple branch validates the pair elements. The
fake env warns on attribute access rather than call, so hasattr/
truthiness branches are diagnosable, with dunder probes excluded; an
unmodelled subscript warns and returns '' instead of a KeyError
discarding the whole capture. Malformed platforms/frameworks values
raise plain InvalidLibrary, giving the non-platform warning branches a
real producer, and their tests use real manifests instead of
monkeypatched raisers. The version-less dependency drop moves to debug:
bundled names (Wire, SPI) made it per-build noise nobody can act on.

tests/unit_tests/test_platformio_extra_script.py

@@ -270,7 +270,7 @@ def test_apply_extra_script_ignores_uncaptured_env_calls(tmp_path, caplog) -> No
     apply_extra_script(c, board_mcu=lambda: "esp8266", pio_platform="espressif8266")
     assert c.data["build"]["flags"] == ["-lsingle"]
     assert "env.Append(UNCAPTURED=...) is not captured" in caplog.text
-    assert "env.Replace(...) is not supported" in caplog.text
+    assert "env.Replace is not supported" in caplog.text
 
 
 def test_apply_extra_script_swallows_script_errors(tmp_path, caplog) -> None:
@@ -378,7 +378,7 @@ def test_unsupported_env_method_warns_once(caplog) -> None:
     )
     env.Replace(CC="clang")
     env.Replace(CC="gcc")
-    assert caplog.text.count("env.Replace(...) is not supported") == 1
+    assert caplog.text.count("env.Replace is not supported") == 1
 
 
 def test_run_extra_script_sys_exit_is_best_effort(tmp_path, caplog) -> None:
@@ -458,10 +458,14 @@ def test_env_get_unknown_key_warns_once(caplog) -> None:
 def test_spaced_linkflag_survives_relexing(tmp_path) -> None:
     """A captured argv token with a space stays one token after lexing."""
     result = ExtraScriptResult(
-        linkflags=["-Wl,-T my linker.ld"], cppflags=["-include my hdr.h"]
+        linkflags=["-Wl,-T my linker.ld"],
+        cppflags=["-include my hdr.h"],
+        cppdefines=[("MSG", '"hello world"'), "PLAIN"],
     )
     flags = captured_as_build_flags(result, library_dir=tmp_path)
     assert lex_build_flags(flags, "test") == [
+        '-DMSG="hello world"',
+        "-DPLAIN",
         "-Wl,-T my linker.ld",
         "-include my hdr.h",
     ]