feat(insights): add custom data color themes

[thmsobrmlr]

Problem

The ability to control the themes and colours of insights and dashboards would be helpful to contextualise them to end users, eg Blue for B2B , green for B2C etc.

Changes

• adds a dataColorTheme prop to insight queries - this will allow overriding themes in insights (no UI, yet)
• adds a project setting to customize themes http://localhost:8000/project/1/settings/environment-product-analytics#data-theme
• adds a basic admin interface for data color themes http://localhost:8000/admin/posthog/datacolortheme/
• adds a storybook story for data colors http://localhost:6006/?path=/story/lemon-ui-colors--data-colors
• doesn't add a color theme adapted for color vision deficiencies - i tested the posthog default theme in various color blindness similators and deemed they work well for most cases. was told that the pm revising these colors had considered color vision deficiencies.
• adds a <ColorGlyph /> component that remembers the last valid color

How did you test this code?

[posthog-bot]

📸 UI snapshots have been updated

16 snapshot changes in total. 0 added, 16 modified, 0 deleted:

• chromium: 0 added, 16 modified, 0 deleted (diff for shard 1)
• webkit: 0 added, 0 modified, 0 deleted

Triggered by this commit.

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[posthog-bot]

📸 UI snapshots have been updated

16 snapshot changes in total. 0 added, 16 modified, 0 deleted:

• chromium: 0 added, 16 modified, 0 deleted (diff for shard 1)
• webkit: 0 added, 0 modified, 0 deleted

Triggered by this commit.

👉 Review this PR's diff of snapshots.