feat: add Solana address creation via WASM

Implement wasm-solana package for Solana address generation using official
Solana SDK crates (solana-pubkey, solana-keypair) compiled to WebAssembly.
This is Phase 1 of replacing JavaScript Solana dependencies to mitigate
npm supply chain attack risks.

Architecture follows wasm-utxo patterns:
- Core types wrap official Solana SDK with extension traits (PubkeyExt, KeypairExt)
- Thin WASM bindings (src/wasm/*.rs) expose types to JavaScript
- TypeScript wrappers (js/*.ts) provide idiomatic camelCase APIs

Components:
- Pubkey: base58 encoding/decoding, is_on_curve() for PDA detection
- Keypair: creation from 32-byte seed or 64-byte Solana secret key format

Build tooling:
- Makefile matching wasm-utxo's wasm-pack workflow
- TypeScript configs for ESM and CJS output

Verified compatibility with BitGoJS sdk-coin-sol test vectors.

Ticket: BTC-2927

Author: lcovar

package-lock.json

@@ -0,0 +1,10 @@
+target/
+node_modules/
+# we actually only track the .ts files
+dist/
+test/*.js
+test/*.d.ts
+js/*.js
+js/*.d.ts
+js/wasm
+.vscode

packages/wasm-solana/.gitignore

@@ -0,0 +1,5 @@
+{
+  "extensions": ["ts", "tsx", "js", "jsx"],
+  "spec": ["test/**/*.ts"],
+  "node-option": ["import=tsx/esm", "experimental-wasm-modules"]
+}

packages/wasm-solana/.mocharc.json

@@ -0,0 +1,5 @@
+dist/
+target/
+js/wasm/
+pkg/
+node_modules/