feat: improvements for the theming scheme of the SDK

[kristian-mkd]

🎯 Goal

• Jira Ticket: PBE-5856
• consolidate and improve the theming options of the SDK

🛠 Implementation details

✅ theme color and options are improved
✅ new variants added (fontSizes, spacingSizes)
✅ new defaults added
✅ colorPalette usages in the SDK are removed
✅ darkColors are removed from SDK, so only one set of colors present in base theme
✅ new alternative theme.get(componentOrPath: string, prop?: keyof Theme['defaults'] | string) method added with unit test coverage

TBD: 🚧 In the next tasks from the Design v2 provide additional fixes in the dogfood app

• PBE-5855-feat/react-native-video-design-v2 will serve as umbrella branch for tasks which are part of this epic

Table with the color name changes for easier reviewing:

old name	new name	value
static_white	base1	palette.grey50
borders	base2	palette.grey300
text_low_emphasis	base3	palette.grey500
static_gray	base4	palette.grey700
static_black	base5	palette.grey950
dark.conent_bg	background1	palette.grey950 + opacityToHex(0.05)
dark_gray	background2	palette.grey800
overlay	background3	palette.grey950 + opacityToHex(0.4)
overlay_dark	background4	palette.grey950 + opacityToHex(0.6)
dark.bars & dark.controls_bg	background5	palette.grey900
static_overlay	background6	palette.grey950 + opacityToHex(0.85)
dark.text_high_emphasis	base1	palette.grey50
dark.borders	base4	palette.grey700
dark.overlay	background3	palette.grey950 + opacityToHex(0.4)

🎨 UI Changes

iOS

Before	After

Android

Before	After

🧪 Testing

☑️ Checklist

• I have signed the Stream CLA (required)
• PR targets the develop branch
• Documentation is updated
• New code is tested in main example apps, including all possible scenarios
  • SampleApp iOS and Android
  • Expo iOS and Android

[santhoshvai]

Please do make sure that all margins, padding, sizes also move to theme when we move to design v2