chore: scaffold PYRE MVP monorepo (structure + docs)

pnpm + TypeScript workspace per design doc §13:
- apps/{web,api,worker} skeletons (Next.js 16, Fastify 5, BullMQ)
- packages/{core,solana,prometheus,db,config} (core has real types/DTOs;
  solana/prometheus are stubs)
- programs/pyre-core placeholder (future Anchor, v1.0)
- docs/: PYRE_MVP_DESIGN (canonical), ARCHITECTURE, SECURITY, TOKEN_CLASSIFICATION
- CLAUDE.md, README, .env.example (no private-key var by design)

Skeleton + docs only — no Solana/business logic yet. All workspaces typecheck clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/solana/src/index.ts

@@ -0,0 +1,94 @@
+/**
+ * @pyre/solana — Solana transaction helpers (STUBS ONLY).
+ *
+ * Responsibilities (§13): token-account parsing, close-account tx builder, burn
+ * tx builder, simulation helpers, and a transaction decoder.
+ *
+ * IMPORTANT (trust rules, §3/§7/§16):
+ * - PYRE never holds private keys; these helpers build **unsigned** transactions
+ *   only. Signing happens client-side in the user's wallet.
+ * - Recovered ATA rent must default to the user's own wallet.
+ * - Every transaction must be simulated and **decoded**, then matched against the
+ *   preview shown to the user before any signature is requested.
+ * - Classic SPL only in the MVP. Skip Token-2022 / NFTs / unsupported layouts.
+ *
+ * Nothing here is implemented yet — every function throws "not implemented".
+ */
+import type { Connection, PublicKey } from "@solana/web3.js";
+import type {
+  TokenAccountDto,
+  BuildCloseEmptyPreview,
+  BuildBurnPreview,
+  BurnItem,
+} from "@pyre/core";
+
+const NOT_IMPLEMENTED = "not implemented";
+
+/**
+ * Parse a wallet's SPL token accounts into classified DTOs.
+ *
+ * TODO: fetch token accounts via RPC, decode account state (balance, decimals,
+ * frozen/delegated, token program), resolve metadata, and hand off to the
+ * classifier in `@pyre/core`. Classic SPL only.
+ */
+export function parseTokenAccounts(
+  _connection: Connection,
+  _wallet: PublicKey,
+): Promise<TokenAccountDto[]> {
+  throw new Error(NOT_IMPLEMENTED);
+}
+
+/**
+ * Build an UNSIGNED transaction that closes the given empty ATAs, returning rent
+ * to the user wallet.
+ *
+ * TODO: assemble CloseAccount instructions, set fee payer + rent destination to
+ * the user, return a base64 transaction plus a matching preview.
+ */
+export function buildCloseEmptyAccountsTx(
+  _connection: Connection,
+  _wallet: PublicKey,
+  _accountAddresses: PublicKey[],
+): Promise<{ transactionBase64: string; preview: BuildCloseEmptyPreview }> {
+  throw new Error(NOT_IMPLEMENTED);
+}
+
+/**
+ * Build an UNSIGNED transaction that burns the given token balances (optionally
+ * closing accounts that become empty).
+ *
+ * TODO: assemble Burn (and optional CloseAccount) instructions, return a base64
+ * transaction plus a matching preview.
+ */
+export function buildBurnTx(
+  _connection: Connection,
+  _wallet: PublicKey,
+  _items: BurnItem[],
+): Promise<{ transactionBase64: string; preview: BuildBurnPreview }> {
+  throw new Error(NOT_IMPLEMENTED);
+}
+
+/**
+ * Simulate a transaction before signing.
+ *
+ * TODO: run `connection.simulateTransaction`, surface logs/errors, and confirm
+ * the simulation succeeds. All transactions must be simulated before signing.
+ */
+export function simulateTransaction(
+  _connection: Connection,
+  _transactionBase64: string,
+): Promise<unknown> {
+  throw new Error(NOT_IMPLEMENTED);
+}
+
+/**
+ * Decode an unsigned transaction so its contents can be matched against the
+ * preview shown to the user (accounts to close, tokens to burn, rent amount,
+ * rent destination, fees, warnings).
+ *
+ * TODO: deserialize the transaction, decode SPL instructions, and return a
+ * structured, human-comparable summary.
+ */
+export function decodeTransaction(_transactionBase64: string): unknown {
+  throw new Error(NOT_IMPLEMENTED);
+}