fix(cli): preserve invoked cwd for local launcher

[ROOOO]

Summary

• preserve the original invoked working directory through nested HAPI launches instead of falling back to the CLI project cwd
• thread that resolved cwd through session bootstrap and local launch paths across supported agents
• add coverage for spawnHappyCLI cwd propagation

Testing

• bun x vitest run src/utils/spawnHappyCLI.test.ts
• bun run typecheck

[github-actions]

Review mode: initial
No issues found in changed lines.
Residual risk: cwd propagation depends on HAPI_INVOKED_CWD; only spawnHappyCLI coverage added.
Testing: Not run (automation).
HAPI Bot

[github-actions]

Findings

• None.

Summary
Review mode: follow-up after new commits
No issues in changed lines.
Residual risk: only spawnHappyCLI unit coverage; getInvokedCwd consumers untested.

Testing

• Not run (automation)

HAPI Bot