Quote an overridden ldscript name on the link line; note the deliberate board-derived --flash_size

The -T script name was the one user-controlled token on the link line
that skipped shell_token, so a space or dollar sign in a
board_build.ldscript override corrupted the emitted linkflags. The
elf2bin comment now records that --flash_size deliberately stays
board-derived, matching PlatformIO (which reads upload.maximum_size,
not the ldscript).

tests/unit_tests/build_gen/test_arduino8266.py

@@ -1342,3 +1342,14 @@ def test_flash_ld_name_honors_ldscript_override(tmp_path: Path) -> None:
     CORE.platformio_options = {"board_build.ldscript": "../evil.ld"}
     with pytest.raises(EsphomeError, match="bare script name"):
         arduino8266._flash_ld_name("nodemcuv2")
+
+
+def test_write_project_quotes_spaced_ldscript_override(tmp_path: Path) -> None:
+    """An overridden script name re-quotes on the link line like every other
+    user token (a space would otherwise split into two argv elements)."""
+    CORE.platformio_options = {"board_build.ldscript": "my script.ld"}
+    paths = _make_framework(tmp_path)
+    _set_flags()
+    content = _write_ninja(paths)
+    assert "'my script.ld'" in content or '"my script.ld"' in content
+    assert "-T my script.ld" not in content