feat(cli): titles, references, JSON output and restoring deleted pastes

[darwin67]

Summary

The second of two stacked PRs. Stacked on #71, whose endpoints it uses. It brings the Rust client and the CLI up to the redesigned paste model.

Client (textbin-client)

• Create takes a CreateOptions struct and sends title and reference_url along with syntax, expiry and visibility.
• Pastes carry their id, title, reference link, share URL, raw URL and timestamps. All of them are optional, so responses from older servers still decode.
• New calls: list_removed_pastes, restore_paste and purge_paste.
• Pastes serialize the way the server represents them: text in data, and binary content as base64.

CLI (textbin)

• create --title … --reference … (alias --ref) prints the server's share link.
• --json on create, show, delete, deleted and restore prints one line of JSON for scripts. This covers the paste commands in RFD 3's "machine-readable --json" item. The auth commands are not covered yet.
• delete tells you how to restore the paste. delete --permanent deletes it for good, including one that was already deleted.
• deleted lists restorable pastes with their reason, purge date and title.
• restore <id> brings a deleted or expired paste back.

Test plan

• cargo fmt --check, cargo clippy --workspace --all-features -- -D warnings
• cargo test --workspace: 61 tests, 0 failures. New tests cover create query params, decoding links, JSON serialization of text and binary pastes, the deleted-collection requests against a stub server, deleted row formatting and argument parsing.
• End to end against a local server: created a paste with a title and reference, then ran show --json, delete, deleted, restore, delete --permanent, and a restore of the purged paste, which returned 404.

🤖 Generated with Claude Code

https://claude.ai/code/session_019fnjMN7WpEjQJD2zveakV6

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Generated by Claude Code

[darwin67]

Oracle review complete: signed off, with no blocking findings in the CLI/client changes. Integrated the reviewed PR71 reference-metadata fix via a history-preserving merge; no Rust code changes were needed. Final validation: cargo fmt --check, cargo clippy --workspace --all-features -- -D warnings, cargo test --workspace, mix precommit (563 ExUnit tests plus JS tests), and mix credo passed. Compatibility note from review: older server responses still decode (wire compatibility), but CreateOptions replaces the previous Rust method argument lists, so downstream Rust callers must migrate; source compatibility is not claimed. Review session: https://ampcode.com/threads/T-01a12594-e2f1-75be-b343-9239564f5c84

Post-push CI is green: memory/local/S3 Elixir tests, Rust tests, formatting/linting, and production-container build passed. Release/publication jobs skipped as expected.