[Look&Feel] Density and Consistency Improvements

[danieldong51]

Description

This PR applies the Look & Feel density and consistency changes to the Observability repository:

1. Use small context menus
2. Use small tabs
3. Standardize paragraph size (15.75px next theme / 14px V7 theme)
4. Use semantic headers (H1s on main pages, H2s on modals/flyouts)
5. Modal/Flyout Typography
6. Buttons for actions, only using primary buttons for primary calls to action
7. Use small padding on popovers

Screenshots

Small context Menu

Scope	Before	After
Dashboards: Overview Actions
Dashboards: Actions
Dashboards: Vis Actions
Dashboards: Vis
Integrations
Notebook: Header Reporting
Notebook: Header Paragraph
Notebook: Header Notebook
Notebook: Add
Notebook: Paragraph
Notebook: Listing
Trace: Save
Trace: Filters
Trace: Actions

Small tabs

Scope	Before	After
Integration: Home
Integration: Details

Paragraph size

Scope	Before	After
Integration: Details
Notebooks: Empty overview
Notebooks: Empty notebook
Notebooks: Timestamp
Notebooks: Created
Notebooks: Quickstart
Traces: Empty
Traces: Map

Semantic Headers

Scope	Before	After
Dashboard: Overview
Dashboard: Title
Integrations: Overview
Integrations: Header
Integrations: Setup
Integrations: Added
Notebooks: Overview
Notebooks: Title
Trace: Trace ID
Trace: Service

Flyouts

Scope	Before	After
Dashboard: Select Vis
Integrations: Upload
Trace: Header
Trace: Span Header

Modals

Scope	Before	After
Dashboard: Create
Dashboard: Error
Dashboard: Error
Dashboard: Samples
Integrations: Delete
Integrations: Delete
Notebooks: Browse Vis
Notebooks: Duplicate
Notebooks: Delete

Check List

• New functionality includes testing.
  • All tests pass, including unit test, integration test and doctest
• New functionality has been documented.
  • New functionality has javadoc added
  • New functionality has user manual doc added
• Commits are signed per the DCO using --signoff

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