feat(auth): add wallet auth telemetry events

[sorinc03]

Summary

• Define shared wallet-link and wallet-auth telemetry event names, outcomes, boundaries, and payload shape in @chordially/types
• Emit sanitized server-side events from API login/logout boundaries and Stellar starter-intent boundary
• Add focused tests proving success, failure, revocation, and starter-intent events exclude emails, passwords, tokens, user-agent strings, and signing artifacts

Testing

• pnpm --filter @chordially/api exec tsx --test tests/wallet-auth-telemetry-424.test.ts
• pnpm --filter @chordially/stellar-service exec tsx --test tests/wallet-auth-telemetry-424.test.ts
• pnpm --filter @chordially/types typecheck
• pnpm --filter @chordially/api typecheck
• pnpm --filter @chordially/stellar-service typecheck
• pnpm --filter @chordially/api lint (passes with existing warnings)
• pnpm --filter @chordially/stellar-service lint
• pnpm --filter @chordially/types lint
• git diff --check

Note: full pnpm --filter @chordially/api test currently has 4 pre-existing lockout expectation failures in auth-330-lockout.test.ts around ACCOUNT_LOCKED / LOGIN_FAILED; the new telemetry tests pass.

Fixes #424