Migrate to @bsky.app/alf package (#9030)

* Add storybook shortcut in dev

* Migrate to alg pkg

* Migrate font_bold to new font_semi_bold

* Migrate font_heavy to font_bold

* Fix old theme refs

* Remove leading util

* Bump

* Revert "Add storybook shortcut in dev"

This reverts commit 7a86195c77fb5d449c7782e64ebabb6addfab919.

* Remove alf script

* Adjust font scale

* Bump

* Bump pkg

* Migrate values from conflicts

* Create default themes outside react

* Use built-in alf utils

* Migrate old font styles

* Remove unused tokens

* Move theme creation to more appropriate file

* Update button colors

* Adjust TextField colors, line heights

src/components/WelcomeModal.tsx

@@ -108,7 +108,7 @@ export function WelcomeModal({control}: WelcomeModalProps) {
                   <Text
                     style={[
                       a.text_2xl,
-                      a.font_bold,
+                      a.font_semi_bold,
                       a.user_select_none,
                       {color: '#354358', letterSpacing: -0.5},
                     ]}>
@@ -127,7 +127,7 @@ export function WelcomeModal({control}: WelcomeModalProps) {
                 <Text
                   style={[
                     gtMobile ? a.text_4xl : a.text_3xl,
-                    a.font_bold,
+                    a.font_semi_bold,
                     a.text_center,
                     {color: '#354358'},
                     web({