Fix some assorted documentation cross-references

Couple or so things I noticed while working on docs.

docs/guide/screens.md

@@ -225,8 +225,8 @@ The main screen is darkened to indicate to the user that it is not active, and o
 It is a common requirement for screens to be able to return data.
 For instance, you may want a screen to show a dialog and have the result of that dialog processed *after* the screen has been popped.
 
-To return data from a screen, call [`dismiss()`][textual.screen.dismiss] on the screen with the data you wish to return.
-This will pop the screen and invoke a callback set when the screen was pushed (with [`push_screen`][textual.app.push_screen]).
+To return data from a screen, call [`dismiss()`][textual.screen.Screen.dismiss] on the screen with the data you wish to return.
+This will pop the screen and invoke a callback set when the screen was pushed (with [`push_screen`][textual.app.App.push_screen]).
 
 Let's modify the previous example to use `dismiss` rather than an explicit `pop_screen`.
 

src/textual/screen.py

@@ -778,7 +778,7 @@ class Screen(Generic[ScreenResultType], Widget):
     def dismiss(self, result: ScreenResultType | Type[_NoResult] = _NoResult) -> None:
         """Dismiss the screen, optionally with a result.
 
-        If `result` is provided and a callback was set when the screen was [pushed][textual.app.push_screen], then
+        If `result` is provided and a callback was set when the screen was [pushed][textual.app.App.push_screen], then
         the callback will be invoked with `result`.
 
         Args:

src/textual/widgets/_tabs.py

@@ -183,11 +183,6 @@ class Tabs(Widget, can_focus=True):
         ALLOW_SELECTOR_MATCH = {"tab"}
         """Additional message attributes that can be used with the [`on` decorator][textual.on]."""
 
-        tabs: Tabs
-        """The tabs widget containing the tab."""
-        tab: Tab
-        """The tab that was activated."""
-
         def __init__(self, tabs: Tabs, tab: Tab) -> None:
             """Initialize event.
 
@@ -195,8 +190,10 @@ class Tabs(Widget, can_focus=True):
                 tabs: The Tabs widget.
                 tab: The tab that was activated.
             """
-            self.tabs = tabs
-            self.tab = tab
+            self.tabs: Tabs = tabs
+            """The tabs widget containing the tab."""
+            self.tab: Tab = tab
+            """The tab that was activated."""
             super().__init__()
 
         @property
@@ -215,16 +212,14 @@ class Tabs(Widget, can_focus=True):
     class Cleared(Message):
         """Sent when there are no active tabs."""
 
-        tabs: Tabs
-        """The tabs widget which was cleared."""
-
         def __init__(self, tabs: Tabs) -> None:
             """Initialize the event.
 
             Args:
                 tabs: The tabs widget.
             """
-            self.tabs = tabs
+            self.tabs: Tabs = tabs
+            """The tabs widget which was cleared."""
             super().__init__()
 
         @property