Clean up env vars automatically added to agent.yaml during init

[Copilot]

Microsoft samples are migrating to FOUNDRY_PROJECT_ENDPOINT (auto-injected by the hosted agent platform), so azd no longer needs to bake AZURE_AI_PROJECT_ENDPOINT / AZURE_OPENAI_ENDPOINT into agent.yaml during init.

Changes

• Remove old env vars from agent.yaml init (init_from_code.go): Stop adding AZURE_OPENAI_ENDPOINT and AZURE_AI_PROJECT_ENDPOINT to the environment_variables section. Model-specific vars like AZURE_AI_MODEL_DEPLOYMENT_NAME are still added when applicable.

• Add FOUNDRY_ env var translation for azd ai agent run* (run.go): Locally running agents now get the same env var names the platform injects into hosted containers:

  AZURE_AI_PROJECT_ENDPOINT  → FOUNDRY_PROJECT_ENDPOINT
  AZURE_AI_PROJECT_ID        → FOUNDRY_PROJECT_ARM_ID
  AGENT_{SVC}_NAME           → FOUNDRY_AGENT_NAME
  AGENT_{SVC}_VERSION        → FOUNDRY_AGENT_VERSION
  

  Per discussion, azd env keys (AGENT_SVC_NAME_NAME, etc.) remain unchanged for multi-agent support — only the process env passed to the running agent gets the FOUNDRY_* aliases.

• Expose ServiceName on ServiceRunContext (helpers.go): Needed to derive the service-specific AGENT_{SVC}_* keys for the FOUNDRY mapping.

• appendEnvVar helper (init_from_code.go): Nil-safe append since EnvironmentVariables is now nil by default instead of pre-populated.

[jongio]

Translates azd env keys to FOUNDRY_* aliases for local-dev parity with hosted containers.

Issues to address:

• run.go:389 - appendFoundryEnvVars can silently override a user-set FOUNDRY_* value when the corresponding AZURE_* key also exists in the azd env

One question: is there a FOUNDRY_* equivalent for AZURE_OPENAI_ENDPOINT? It's dropped from agent.yaml but doesn't appear in the translation mapping.

[jongio]

[MEDIUM] If FOUNDRY_PROJECT_ENDPOINT is already set in the azd env (or inherited from the shell), this appends a duplicate entry. Most platforms use last-value-wins, so the translation silently overrides the explicit value.

Consider skipping when the foundry key already exists:

Suggested change

	for _, m := range staticMappings {
	for _, m := range staticMappings {
	if v := azdEnv[m.azdKey]; v != "" {
	if _, exists := azdEnv[m.foundryKey]; !exists {
	env = append(env, fmt.Sprintf("%s=%s", m.foundryKey, v))
	}
	}
	}

Same pattern applies to the agentMappings loop below.