feat: complete Groq provider integration and add Kimi K2 model (#978)

* feat: complete Groq provider integration and add Kimi K2 model

- Add missing getRequiredApiKeyName() method to GroqProvider class
- Register GroqProvider in ai-services-unified.js PROVIDERS object
- Add Groq API key handling to config-manager.js (isApiKeySet and getMcpApiKeyStatus)
- Add GROQ_API_KEY to env.example with format hint
- Add moonshotai/kimi-k2-instruct model to Groq provider ($1/$3 per 1M tokens, 16k max)
- Fix import sorting for linting compliance
- Add GroqProvider mock to ai-services-unified tests

Fixes missing implementation pieces that prevented Groq provider from working.

* chore: improve changeset

---------

Co-authored-by: Ben Vargas <ben@example.com>
Co-authored-by: Ralph Khreish <35776126+Crunchyman-ralph@users.noreply.github.com>

scripts/modules/supported-models.json

@@ -295,6 +295,16 @@
 		}
 	],
 	"groq": [
+		{
+			"id": "moonshotai/kimi-k2-instruct",
+			"swe_score": 0.66,
+			"cost_per_1m_tokens": {
+				"input": 1.0,
+				"output": 3.0
+			},
+			"allowed_roles": ["main", "fallback"],
+			"max_tokens": 16384
+		},
 		{
 			"id": "llama-3.3-70b-versatile",
 			"swe_score": 0.55,