fix(figspec): fix generated completions for azd extension install

[Copilot]

Related to #8416 and microsoft/vscode#321221

Summary

This PR updates azd's Fig spec generator to preserve VS Code's corrected completions for azd extension install.

Issue

The generator still emitted the legacy template: 'filepaths' fallback, while the VS Code spec now combines extension ID suggestions with .zip file paths. Regenerating the spec could therefore overwrite the fix from microsoft/vscode#321221.

Changes

• Adds support for rendering multiple generators on a single argument.
• Generates both extension ID suggestions and .zip-only file path suggestions for azd extension install.
• Emits the VS Code filepaths helper import and removes the obsolete argument template field.
• Documents combined generators and refreshes the generated spec snapshot.

Behavior at a glance

Scenario	Before	After
azd extension install <arg>	Extension IDs plus unrestricted legacy file path completion	Extension IDs plus .zip file path completion

Testing

Updated unit coverage for multi-generator rendering and extension install customization, along with the generated Fig spec snapshot.

[Copilot]

Pull request overview

Updates azd’s Fig spec generation (used for VS Code terminal IntelliSense) so azd extension install completions can combine extension-ID suggestions with .zip-scoped file path suggestions using VS Code’s filepaths helper API.

Changes:

• Extends the Fig spec arg model to support multi-generator args via a new Arg.Generators []string field (taking precedence over Arg.Generator) and removes the unused Template field.
• Updates the TypeScript renderer to emit generators: [...] when multiple generators are present and to add a filepaths helper import to the generated spec output.
• Adds a FigGenFilepathsZip constant and updates azd extension install customization, docs, and the Fig spec snapshot accordingly.

Show a summary per file

File	Description
cli/azd/internal/figspec/typescript_renderer.go	Renders multi-generator args and injects a filepaths import into generated TypeScript.
cli/azd/internal/figspec/typescript_renderer_test.go	Updates renderer tests for multi-generator output and import presence.
cli/azd/internal/figspec/types.go	Adds Arg.Generators []string and removes the dead Template field.
cli/azd/internal/figspec/fig_generators.go	Adds FigGenFilepathsZip and the filepaths import constant.
cli/azd/internal/figspec/customizations.go	Uses the new multi-generator form for azd extension install.
cli/azd/internal/figspec/customizations_test.go	Updates customization assertions for multi-generator args.
cli/azd/docs/fig-spec.md	Documents the new multi-generator usage and filepaths import behavior; adds missing generator doc row.
cli/azd/cmd/testdata/TestFigSpec.ts	Snapshot updated to include the new import preamble and generator array form.

Review details

Comments suppressed due to low confidence (1)

cli/azd/internal/figspec/typescript_renderer.go:59

• azd-code-reviewer: ToTypeScript currently injects filepathsHelperImport unconditionally. That hard-codes the generated spec to VS Code’s repo layout even when the spec doesn’t use filepaths(...) (e.g., TestToTypeScript_Empty), and can also become a TS compile/lint failure if filepaths usage is removed later (unused/missing-module import). Consider emitting this import only when the rendered spec actually contains a filepaths( generator (or when FigGenFilepathsZip is present in any arg).

	data := map[string]string{
		"Name":        s.Name,
		"Description": s.Description,
		"Import":      filepathsHelperImport,
		"Generators":  figGeneratorDefinitionsTS,
		"Subcommands": renderSubcommands(s.Subcommands, 2),
		"Options":     renderOptions(s.Options, 2, false),
	}

• Files reviewed: 8/8 changed files
• Comments generated: 1
• Review effort level: Low

[JeffreyCA]

/azp run azure-dev - cli

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[Copilot]

Review details

• Files reviewed: 8/8 changed files
• Comments generated: 0 new
• Review effort level: Medium

[jongio]

One optional note below on the generated filepaths import. Otherwise this looks correct: the old Template field is fully removed with no remaining references, and the multi-generator rendering, updated tests, and regenerated Fig spec snapshot all pass locally.

[jongio]

This injects the filepaths import into every generated spec, whether or not any arg actually uses filepaths. It's fine today because azd extension install always needs it, but if that usage ever goes away the generated spec keeps an unused import, which trips no-unused-vars in the VS Code repo where the spec lives. Consider gating the import on whether the rendered output actually references filepaths so the preamble stays in sync with real usage.