feat(cli): aligned prefixes, colors, spinner, noise filtering

[HumanBean17]

Summary

• Align stderr prefixes between cocoindex ([vectors]) and graph builder ([graph]) stages for consistent output
• Add TTY-aware ANSI styling (bold, cyan, green, red) for phase tags and ✓/✗ markers
• Add braille spinner animation during the cocoindex phase (was a "black box" with no progress for 30+ seconds)
• Filter known noise lines from cocoindex/lance stderr (lance::, FutureWarning, Loading weights, brownfield events)
• Add --verbose (raw output) / --quiet (silent stderr) flags for three-tier output model
• Emit styled completion lines from parent process so colors work correctly with piped subprocess stderr

Output design

Default (TTY): Colored tags + spinner + filtered

java-codebase-rag init · source=/repo · index=/idx
⠋ [vectors] running · cocoindex update
✓ [vectors] finished · 34.86s

[graph] pass 1 · parsing Java files
[graph] pass 1 · parsed 130 files in 0.11s: 140 types, 606 members
...
✓ [graph] done

✓ java-codebase-rag init · finished in 60.83s

Pipe/CI: Same text, no ANSI codes, no spinner

--verbose: Raw unfiltered output

--quiet: Nothing on stderr

Test plan

• pytest tests/test_cli_quiet_parity.py tests/test_cli_progress_stdout_invariant.py tests/test_java_codebase_rag_cli.py — 52 passed, 3 skipped
• ruff check passes
• Manual: java-codebase-rag init --source-root <repo> --index-dir /tmp/test — verify colors, spinner, aligned prefixes
• Manual: java-codebase-rag init --quiet — verify silent stderr
• Manual: java-codebase-rag init --verbose — verify raw unfiltered output
• Manual: java-codebase-rag init 2>&1 | cat — verify no ANSI codes in pipe

🤖 Generated with Claude Code