chore(release): prepare 0.6.6

[clabby]

Summary

• bump every workspace crate from 0.6.5 to 0.6.6
• update internal workspace dependency versions
• refresh the workspace lockfile

Testing

• just check-fmt
• just clippy
• just test (946 tests)

Stack

1. feat(prompt): link local images with Markdown #179 — Markdown image-link prompting
2. fix(tui): render local images reliably #182 — nonblocking native image rendering
3. This PR

Depends on #182. No matching open issue exists to close.

[codspeed-hq]

Merging this PR will not alter performance

✅ 18 untouched benchmarks
⏩ 31 skipped benchmarks¹

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_{Comparing cl/release-0.6.6 (7d495f0) with main (7f9a588)²}

Footnotes

1. 31 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

2. No successful run was found on cl/image-rendering (ab9ca94) during the generation of this report, so main (7f9a588) was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩