Make component return types honest; drop str/mark_safe leftovers

Cleanup of hacky leftovers from the node-tree migration (no behaviour
change):

- Return annotations: the component builders return Node subtrees, not
  SafeText strings, but ~40 functions still declared `-> SafeText`. Correct
  them to `-> Node` across filters / search_select / date_range_picker /
  domain. The genuine string returners keep `-> SafeText`: the Alpine
  selectors (GameStatusSelector / SessionDeviceSelector, which build f-string
  markup) and the script-tag helpers (CsrfInput / ModuleScript /
  ExternalScript / StaticScript).
- layout.render_page / layout.Page / AddForm now accept `Node` in their
  `content` / `scripts` / `fields` parameters (TYPE_CHECKING import in
  layout to avoid the components import cycle), matching what views already
  pass.
- session._session_fields builds a `Fragment(*rows, separator="\n")` instead
  of `mark_safe("\n".join(str(row) ...))` — keeps the tree intact so media
  could bubble, per the Fragment convention.
- Inline SVG icon children use `Safe(...)` nodes instead of `mark_safe(...)`
  strings (filters mode-toggle + collapse icons, date_range_picker calendar
  icon).
- _filter_field reads the widget's own id from its node `.attributes`
  (`_widget_id`) for the label's `for`, dropping the superfluous `for_widget`
  argument that always rendered `for="None"`. Removes the two TODOs whose
  premise ("the Component function can't expose the id") the class/node
  refactor retired, plus RangeSlider's dead commented-out Label block.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

common/components/domain.py

@@ -6,7 +6,7 @@ from django.template.defaultfilters import floatformat
 from django.urls import reverse
 from django.utils.safestring import SafeText, mark_safe
 
-from common.components.core import HTMLTag
+from common.components.core import HTMLTag, Node
 from common.components.primitives import (
     A,
     Div,
@@ -22,7 +22,7 @@ def GameLink(
     game_id: int,
     name: str = "",
     children: list[HTMLTag] | HTMLTag | None = None,
-) -> SafeText:
+) -> Node:
     """Link to a game's detail page. Uses children (slot) if provided, otherwise name."""
     from django.urls import reverse
 
@@ -58,7 +58,7 @@ def GameStatus(
     status: str = "u",
     display: str = "",
     class_: str = "",
-) -> SafeText:
+) -> Node:
     """Colored status dot with label. Status codes: u/p/f/a/r."""
     children = children or []
     outer_class = (
@@ -82,7 +82,7 @@ def GameStatus(
 
 def PriceConverted(
     children: list[HTMLTag] | HTMLTag | None = None,
-) -> SafeText:
+) -> Node:
     """Wrap content in a span that indicates the price was converted."""
     children = children or []
     return Span(
@@ -94,7 +94,7 @@ def PriceConverted(
     )
 
 
-def LinkedPurchase(purchase: Purchase) -> SafeText:
+def LinkedPurchase(purchase: Purchase) -> Node:
     link = reverse("games:view_purchase", args=[int(purchase.id)])
     link_content = ""
     popover_content = ""
@@ -145,7 +145,7 @@ def NameWithIcon(
     session: Session | None = None,
     linkify: bool = True,
     emulated: bool = False,
-) -> SafeText:
+) -> Node:
     _name, platform, final_emulated, create_link, link = _resolve_name_with_icon(
         name, game, session, linkify
     )
@@ -203,7 +203,7 @@ def _resolve_name_with_icon(
     return _name, platform, final_emulated, create_link, link
 
 
-def PurchasePrice(purchase) -> SafeText:
+def PurchasePrice(purchase) -> Node:
     return Popover(
         popover_content=f"{floatformat(purchase.price)} {purchase.price_currency}",
         wrapped_content=f"{floatformat(purchase.converted_price)} {purchase.converted_currency}",