feat: stable tools utxo-hd commands in client CLI

[jpraynaud]

Content

This PR includes the stabilization of the tools utxo-hd commands in the client CLI.

Pre-submit checklist

• Branch
  • Crates versions are updated (if relevant)
  • CHANGELOG file is updated (if relevant)
  • Commit sequence broadly makes sense
  • Key commits have useful messages
• PR
  • All check jobs of the CI have succeeded
  • Self-reviewed the diff
  • Useful pull request description
  • Reviewer requested
• Documentation
  • Update documentation website (if relevant)

Issue(s)

Relates to #2625

[Copilot]

Pull Request Overview

This PR stabilizes the tools utxo-hd commands in the Mithril client CLI by removing the experimental/unstable flag requirement. The commands are now available as stable functionality without needing the --unstable flag.

• Removed unstable flag requirement for tools utxo-hd commands
• Updated documentation to reflect stable status
• Version bump to 0.12.30

Reviewed Changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
mithril-client-cli/src/main.rs	Removed unstable feature gate for Tools commands
mithril-client-cli/src/commands/tools/mod.rs	Updated command description to remove "[unstable]" marker
mithril-client-cli/src/commands/cardano_db/shared_steps.rs	Updated example command to remove --unstable flag
mithril-client-cli/Cargo.toml	Version bump from 0.12.29 to 0.12.30
docs/website/root/manual/getting-started/bootstrap-cardano-node.md	Updated documentation examples to remove --unstable flag
docs/website/root/manual/develop/nodes/mithril-client.md	Updated help text to remove "[unstable]" marker
CHANGELOG.md	Added entry for stable tools utxo-hd support
.github/workflows/test-client.yml	Updated CI tests to remove --unstable flag

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[github-actions]

Test Results

    4 files  ±0    164 suites  ±0   23m 9s ⏱️ -13s
2 180 tests  - 1  2 180 ✅  - 1  0 💤 ±0  0 ❌ ±0 
6 702 runs   - 4  6 702 ✅  - 4  0 💤 ±0  0 ❌ ±0 

Results for commit 1120444. ± Comparison against base commit d1a7dd2.

[turmelclem]

LGTM 👍