chore: pi family 0.85.1 -> 0.87.1 (finishTurn, transcript contexts, typebox 1.3.27)

Mechanical fallout only; semantic deltas flagged in the wave report:
- shouldStopAfterTurn -> finishTurn ({action:'end'} wrap; loop order verified
  equivalent for Wave C stranding)
- transcript rework: seeded leading SystemMessage filtered at both
  state.messages read seams (ui-stream settleWith, pi-run slice); prompt
  and tool declarations now ride the transcript
- streamOnce sites normalizeContext() (Context -> TranscriptContext)
- AgentToolResult details / ToolCall.arguments JsonValue narrowing (casts)
- AUTH_PROVIDER_KEYS regenerated (meta added); glm-5.3-flash price pin
  follows the 0.87.1 catalog (0.15/0.5/0.05)
- vanish probe: 0/12 vs 2/6 baseline; live smoke green on PORT=3004

src/core/auth-keys.ts

@@ -95,6 +95,7 @@ export const AUTH_PROVIDER_KEYS: readonly AuthProviderInfo[] = [
 	{ id: "groq", envVar: "GROQ_API_KEY", label: "Groq" },
 	{ id: "huggingface", envVar: "HF_TOKEN", label: "Hugging Face" },
 	{ id: "kimi-coding", envVar: "KIMI_API_KEY", label: "Kimi For Coding" },
+	{ id: "meta", envVar: "META_API_KEY", label: "Meta" },
 	{ id: "minimax", envVar: "MINIMAX_API_KEY", label: "MiniMax" },
 	{ id: "minimax-cn", envVar: "MINIMAX_CN_API_KEY", label: "MiniMax CN" },
 	{ id: "mistral", envVar: "MISTRAL_API_KEY", label: "Mistral" },

src/core/native-messages.ts

@@ -117,7 +117,9 @@ export function newAnswerResult(
 		toolCallId,
 		toolName,
 		content: [{ type: "text", text: JSON.stringify(answer) }],
-		details: answer,
+		// 0.87.1 narrowed ToolResultMessage.details to JsonRepresentation —
+		// our payloads are JSON-safe answer structures, so the cast is honest.
+		details: answer as ToolResultMessage["details"],
 		isError: false,
 		timestamp: Date.now(),
 	};