fix(web_core)!: namespace the basic catalog custom element tags

[josemontespg]

Summary

Namespaces the 13 remaining basic catalog custom element tags to a2ui-basic-* (such as renaming a2ui-card to a2ui-basic-card). This completes the namespace migration for the basic catalog and prevents global custom element registration collisions.

Problem

Custom element tag names share a single global browser registry (window.customElements).

When an application imports @a2ui/web_core/v0_9/basic_catalog, components eagerly register their custom element tags. Thirteen components previously used short, un-namespaced tags like a2ui-card, a2ui-icon, a2ui-modal, and a2ui-audioplayer.

If a host application or another library on the page already registered an element with any of those names, the browser throws an error during module evaluation:

NotSupportedError: Failed to execute 'define' on 'CustomElementRegistry':
the name "a2ui-audioplayer" has already been used with this registry

Because registration occurs at import time, this error blocks the host application from loading.

Additionally, five basic catalog components (Text, Button, TextField, Row, and Column) had already been migrated to a2ui-basic-* in earlier releases. The remaining thirteen components were left un-namespaced, creating an inconsistent naming scheme across the catalog.

Solution

• Rename the remaining 13 custom element tags to a2ui-basic-*:
  Both the @customElement decorator and the exported WebComponentImplementation.tagName are updated together across all 13 components:

  Old Tag	New Tag
  a2ui-audioplayer	a2ui-basic-audioplayer
  a2ui-card	a2ui-basic-card
  a2ui-checkbox	a2ui-basic-checkbox
  a2ui-choicepicker	a2ui-basic-choicepicker
  a2ui-datetimeinput	a2ui-basic-datetimeinput
  a2ui-divider	a2ui-basic-divider
  a2ui-icon	a2ui-basic-icon
  a2ui-image	a2ui-basic-image
  a2ui-list	a2ui-basic-list
  a2ui-modal	a2ui-basic-modal
  a2ui-slider	a2ui-basic-slider
  a2ui-tabs	a2ui-basic-tabs
  a2ui-video	a2ui-basic-video

• Update CSS selectors and tests: Updates internal tag selectors in component stylesheets (a2ui-basic-card { ... }), component unit tests, and Lit explorer integration tests.

• Enforce naming and type safety in tests: In catalog.test.ts, tests assert that every component in basicCatalog has a tagName prefixed with a2ui-basic- and resolves to an instanceof A2uiLitElement.

• Add missing type annotations: Explicitly types A2uiModal and A2uiTextField with WebComponentImplementation to ensure compile-time verification of tagName.

• Preserve CSS class names: CSS class names (such as .a2ui-card and .a2ui-icon) are intentionally left unchanged, preserving the shared styling and theming contract used across the Web Core, Lit, React, and Angular renderers.

Verification

• yarn --cwd renderers/web_core test passes (563 tests).
• Lit explorer integration suite passes (138 of 138 tests).
• yarn --cwd renderers/lit test:unit, yarn --cwd renderers/react test, and full renderer topological build pass.

Pre-launch Checklist

• I read the Contributors Guide.
• My code changes have tests.

[gemini-code-assist]

Code Review

This pull request renames the custom element tag names in the basic catalog to use the a2ui-basic- prefix (e.g., renaming a2ui-icon to a2ui-basic-icon), updating the components, their tests, and the explorer tests accordingly. It also adds a test in catalog.test.ts to verify that all basic catalog components are registered and correctly namespaced. The review feedback suggests importing and applying the WebComponentImplementation type to the A2uiModal export in Modal.ts for consistency and type safety.