fix: surface catalog ID in PromptBuilder

[gspencergoog]

Description

This PR Fixes #900 by surfacing the catalog ID in the system prompt generated by PromptBuilder when it is provided in the Catalog.

Changes

• packages/genui/lib/src/facade/prompt_builder.dart:
  • Added a line to the system prompt: The active catalog ID is: "${catalog.catalogId}". if catalog.catalogId is not null.
• packages/genui/test/facade/prompt_builder_test.dart:
  • Added a test to verify that the catalog ID is surfaced.
  • Removed the test for null fallback as the implementation was changed by the user to not include the line when null.
• packages/genui/test/facade/prompt_builder_test.golden/:
  • Updated all 8 golden files to reflect the new prompt content.

Impact & Risks

• No breaking changes.
• Minimal risk.

Testing

• Ran prompt_builder_test.dart and verified that all 10 tests pass.

[gemini-code-assist]

Code Review

This pull request updates the _BasicPromptBuilder to include the active catalog ID in the system prompt and updates the associated tests and golden files. Review feedback identifies a prompt injection vulnerability due to the lack of sanitization on the catalogId and suggests escaping quotes and newlines. It also recommends adding a test case to handle scenarios where the catalog ID is null to ensure consistent behavior.