Spike: PTY-based Claude Code integration with multi-agent concurrency

Proves that spawning `claude -p` in a pseudo-terminal from Rust gets Max
subscription billing (apiKeySource: "none", rateLimitType: "five_hour")
instead of per-token API charges. Concurrent agents run in parallel PTY
sessions with session resumption via --resume for multi-turn conversations.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/Cargo.toml

@@ -22,6 +22,8 @@ rust-embed = { workspace = true }
 mime_guess = { workspace = true }
 homedir = { workspace = true }
 serde_yaml = "0.9"
+portable-pty = { workspace = true }
+strip-ansi-escapes = { workspace = true }
 
 
 [dev-dependencies]