Standardize VS Code extension recommendations across Azure Local repos

[kristopherjturner]

Summary

Audit the Azure Local repositories to determine the minimum recommended VS Code extensions for each repo, move those recommendations into repo-local .vscode/extensions.json files, and remove repo-specific extension recommendations from the .code-workspace files.

Why

Today extension recommendations are defined in each repo's .code-workspace file. That works when the workspace file is opened, but it does not help when a repository is cloned and opened by itself on another machine.

Using .vscode/extensions.json in each repository is the better default for repo-specific recommendations because it works in both cases:

• the repository is opened by itself as a single-folder workspace
• the repository is included in the broader Azure Local multi-root workspace

Workspace-level recommendations in .code-workspace should only remain if there are truly workspace-wide extensions that are not naturally owned by any single repo.

Scope

• Review current extension recommendations across all Azure Local repositories
• Identify the minimum recommended extension set for each repository
• Create .vscode/extensions.json in each repository that needs recommendations
• Remove repo-specific extensions.recommendations blocks from the .code-workspace files after migration
• Verify recommendations appear when opening a repo standalone and when opening the full Azure Local workspace
• Update contributor documentation if needed to explain where extension recommendations now live

Acceptance Criteria

• Every repository has a reviewed minimum extension recommendation set
• Repo-specific recommendations live in .vscode/extensions.json
• .code-workspace files no longer duplicate repo-specific extension recommendations
• Opening any individual repo surfaces the appropriate recommendations
• Opening the full Azure Local workspace still surfaces the appropriate recommendations
• Documentation reflects the chosen convention

Notes

Current state: extension recommendations exist in the .code-workspace files across the repos and there are no existing .vscode/extensions.json files.