Reject edge whitespace and controls in icon keys instead of trimming

validate_icon stripped the whole value before validating, so
`emoji:🐕 `, `emoji:🐕\n` and `emoji:🐕\x1c` were silently accepted as
`emoji:🐕`. Validate the raw namespace, name and emoji payload; a
whitespace-only value still clears the icon. Padded keys such as
`lucide:dog ` are now rejected naming `icon` (NQ-241-3).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

custom_components/nestquest/core/icons.py

@@ -55,7 +55,9 @@ def validate_icon(value: object) -> str | None:
     """Return the canonical namespaced icon key, or raise naming ``icon``.
 
     ``None`` or an empty/whitespace-only string returns ``None`` (the
-    icon is cleared).  A value with no ``:`` is a legacy bare Lucide
+    icon is cleared).  Otherwise the raw value is validated untrimmed, so
+    edge whitespace or control characters are rejected rather than
+    silently stripped.  A value with no ``:`` is a legacy bare Lucide
     name and is stored as ``lucide:<value>``.  An unknown namespace, an
     empty or malformed name, or an invalid emoji payload raises
     ValueError.
@@ -64,17 +66,16 @@ def validate_icon(value: object) -> str | None:
         return None
     if not isinstance(value, str):
         raise ValueError(f"icon must be a string, got {value!r}")
-    trimmed = value.strip()
-    if not trimmed:
+    if not value.strip():
         return None
 
-    namespace, separator, name = trimmed.partition(":")
+    namespace, separator, name = value.partition(":")
     if not separator:
-        if not _is_kebab_name(trimmed):
+        if not _is_kebab_name(value):
             raise ValueError(
                 f"icon must be a lowercase kebab name, got {value!r}"
             )
-        return f"{ICON_NAMESPACE_LUCIDE}:{trimmed}"
+        return f"{ICON_NAMESPACE_LUCIDE}:{value}"
 
     if namespace not in ICON_NAMESPACES:
         raise ValueError(
@@ -93,7 +94,7 @@ def validate_icon(value: object) -> str | None:
             f"icon {namespace} name must be a lowercase kebab name, "
             f"got {value!r}"
         )
-    return trimmed
+    return value
 
 
 def normalize_icon_for_read(value: str | None) -> str | None:

tests/test_core_icons.py

@@ -34,8 +34,6 @@ def test_namespace_and_cap_constants() -> None:
         ("emoji:" + "⭐" * EMOJI_MAX_CODE_POINTS, "emoji:" + "⭐" * 8),
         # Legacy bare Lucide names normalize to the lucide namespace.
         ("dog", "lucide:dog"),
-        ("  toy-box  ", "lucide:toy-box"),
-        ("  fa:dog  ", "fa:dog"),
     ],
 )
 def test_validate_icon_accepts(value: str, expected: str) -> None:
@@ -72,6 +70,14 @@ def test_validate_icon_clears(value: str | None) -> None:
         "emoji:a&b",  # entity start
         "emoji:🐕\x00",  # control character
         "emoji:🐕\x07🐕",  # control character between emoji
+        # Edge whitespace/controls are part of the value, never trimmed away.
+        "emoji:🐕 ",  # trailing space
+        "emoji:🐕\n",  # trailing newline
+        "emoji:🐕\x1c",  # trailing control character (str.strip() eats it)
+        " emoji:🐕",  # leading space
+        "lucide:dog ",  # trailing space
+        "  fa:dog  ",  # padded namespaced key
+        "  toy-box  ",  # padded legacy bare name
     ],
 )
 def test_validate_icon_rejects_naming_the_field(value: str) -> None:

tests/test_quest_definitions.py

@@ -106,7 +106,7 @@ def test_create_one_child_one_window(tmp_path) -> None:
             [child.id],
             ["morning"],
             description="  Twice daily  ",
-            icon="  lucide:tooth  ",
+            icon="lucide:tooth",
         )
         assert isinstance(result, CreatedQuestDefinition)
         definition = result.definition
@@ -625,7 +625,7 @@ def test_edit_title_description_icon(tmp_path) -> None:
             created.definition.id,
             title="  Floss  ",
             description="  New description  ",
-            icon="  fa:new  ",
+            icon="fa:new",
         )
         assert result.definition.title == "Floss"
         assert result.definition.description == "New description"